A STUDY ON INCREASING THE SHELF LIFE OF

SUGARCANE JUICE AND JAGGERY USING HURDLE

TECHNOLOGY

BY

SNEH SANKHLA

B.A. Sc (FOOD TECHNOLOGY)

THESIS SUBMITTED TO ACHARYA N.G. RANGA AGRICULTURAL UNIVERSITY

IN PARTIAL FULFILMENT OF THE REQUIREMENTS FOR THE AWARD OF THE DEGREE OF

MASTER OF SCIENCE IN FOOD SCIENCE AND TECHNOLOGY

POST GRADUATE AND RESEARCH CENTRE

INTERFACULTY P.G. PROGRAMME IN FOOD SCIENCE & TECHNOLOGY ACHARYA N. G. RANGA AGRICULTURAL UNIVERSITY

RAJENDRANAGAR, HYDERABAD – 500 030.

January, 2011

CERTIFICATE

Ms. SNEH SANKHLA has satisfactorily prosecuted the course of research and

that the thesis entitled, “A STUDY ON INCREASING THE SHELF LIFE OF

SUGARCANE JUICE AND JAGGERY USING HURDLE TECHNOLOGY”

submitted, is the result of original research work and is of sufficiently high standard to

warrant its presentation to the examination, I also certify that the thesis or part thereof

has not been previously submitted by her for a degree of any university.

Date: (Dr. (Mrs.) ANURAG CHATURVEDI)

Place: Hyderabad Chairman

CERTIFICATE

This is to certify that the thesis entitled “A STUDY ON INCREASING THE

SHELF LIFE OF SUGARCANE JUICE AND JAGGERY USING HURDLE

TECHNOLOGY” submitted in partial fulfillment of the requirement for the degree of

MASTER OF SCIENCE IN FOOD SCIENCE AND TECHNOLOGY of the

Acharya N. G. Ranga Agricultural University, Hyderabad is record of the bonafide

research work carried out by Ms. SNEH SANKHLA under my guidance and

supervision. The subject of the thesis has been approved by the student’s Advisory

Committee.

No part of the thesis has been submitted for any degree or diploma. The

published part has been fully acknowledged by the author of the thesis.

(Dr. (Mrs.) ANURAG CHATURVEDI)

Chairman of the Advisory Committee. Thesis approved by the Student’s advisory committee.

Chairman : Dr. (Mrs.) ANURAG CHATURVEDI _____________________ Associate Dean and Professor Department of Foods and Nutrition College of Home Science Saifabad, Hyderabad. Member : Dr. (Mrs.) K. APARNA _____________________ Assistant Professor Department of Foods and Nutrition PG and Research Centre ANGRAU, Rajendranagar, Hyderabad. Member : Dr. K. DHANLAKSHMI _____________________ Associate Professor Department of Microbiology, College of Veterinary Science Rajendranagar, Hyderabad.

DECLARATION I, SNEH SANKHLA, hereby declare that the thesis entitled “A STUDY ON

INCREASING THE SHELF LIFE OF SUGARCANE JUICE AND JAGGERY

USING HURDLE TECHNOLOGY” submitted to Acharya N. G. Ranga Agricultural

University for the degree of MASTER OF SCIENCE IN FOOD SCIENCE AND

TECHNOLOGY is a result of the original research work done by me. I also declare

that the thesis or part thereof has not been published earlier elsewhere in any manner.

Date: (SNEH SANKHLA)

Place: Hyderabad I.D. No. : FST/2008-003

CONTENTS

CHAPTER TITLE PAGE No.

I INTRODUCTION 1

II REVIEW OF LITERATURE 6

III MATERIAL AND METHODS 32

IV RESULTS AND DISCUSSION 44

V SUMMARY AND CONCLUSION 102

LITERATURE CITED 109

APPENDIX 121

LIST OF TABLES

TABLE No. TITLE PAGE

No.

2.1 Nutritive value of sugarcane juice per 100ml 7

2.2 Carbohydrate composition of sugarcane juice 7

2.3 Mineral concentration in sugarcane juice. 8

2.4 Non – nitrogenous organic acid present in cane juice. 9

2.5 Amino acid composition of cane juice 9

4.1 Composition of sugarcane juice 45

4.2 Moisture content of sugarcane juice during storage 47

4.3 Ascorbic acid content of sugarcane juice during storage 51

4.4 Reducing sugar content of sugarcane juice during storage 55

4.5 Total sugar content of sugarcane juice during storage 59

4.6 Mineral estimation of sugarcane juice before and after storage 62

4.7 Viable bacterial count (value in 106) in sugarcane juice during storage 65

4.8 Viable mold count (value in 105) in sugarcane juice during storage 68

4.9 Color and appearance of sugarcane juice during storage 72

4.10 Flavor of sugarcane juice during storage 76

4.11 Taste of sugarcane juice during storage 80

4.12 Overall acceptability of sugarcane juice during storage 84

4.13 Composition of jaggery 87

4.14 Moisture content of jaggery during storage 88

4.15 Reducing sugars of jaggery during storage 90

4.16 Sucrose content of jaggery during storage. 91

4.17 Mineral estimation of jaggery before and after storage 91

4.18 Viable bacterial count in jaggery during storage (value in 106) 93

4.19 Viable yeast and mold count in jaggery storage studies (value in 103) 95

4.20 Colour of jaggery during storage 95

4.21 Texture of jaggery during storage

97

4.22 Taste of jaggery during storage 98

4.23 Overall acceptability of jaggery during storage. 98

LIST OF FIGURES

FIGURE No. TITLE PAGE

No.

4.1 Moisture content of sugarcane juice stored at room temperature 48

4.2 Moisture content of sugarcane juice stored at low temperature 49

4.3 Ascorbic acid content of sugarcane juice stored at room temperature 52

4.4 Ascorbic acid content of sugarcane juice stored at low temperature 53

4.5 Reducing sugars in cane juice stored at room temperature 56

4.6 Reducing sugars in cane juice stored at low temperature 57

4.7 Total sugar content of sugarcane juice stored at room temperature 60

4.8 Total sugar content of sugarcane juice stored at low temperature 61

4.9 Viable bacterial count (value in 106) in sugarcane juice stored at room temperature 66

4.10 Viable bacterial count (value in 106) in sugarcane juice stored at low temperature 67

4.11 Viable mold count (value in 105) in sugarcane juice stored at room temperature 69

4.12 Viable mold count (value in 105) in sugarcane juice stored at low temperature 70

4.13 Changes in color of sugarcane juice stored at room temperature 73

4.14 Changes in color of sugarcane juice stored at low temperature 74

4.15 Changes in flavor of sugarcane juice stored at room temperature. 77

4.16 Changes in flavor of sugarcane juice stored at low temperature 78

4.17 Changes in taste of sugarcane juice stored at room temperature. 81

4.18 Changes in taste of sugarcane juice stored at low temperature. 82

4.19 Changes in overall acceptability of sugarcane juice stored at room temperature. 85

4.20 Changes in overall acceptability of sugarcane juice stored at low temperature. 86

4.21 Moisture content of jaggery during storage. 89

4.22 Reducing sugars of jaggery during storage. 89

4.23 Sucrose content during shelf life storage. 92

4.24 Viable bacterial count in jaggery during storage. (Value in 106) 94

4.25 Viable yeast and mold count in jaggery during storage. (value in 103) 94

4.26 Changes in Colour of jaggery during storage. 96

4.27 Changes in texture of jaggery during storage. 96

4.28 Changes in taste of jaggery during storage. 99

4.29 Changes in overall acceptability of jaggery during storage. 99

LIST OF PLATES

PLATE No. TITLE PAGE

No.

1 Extraction of sugar cane juice 33

2 Preserved sugar cane juice packed in glass bottles used in the present study 33

3 Preserved sugar cane juice packed in PET bottles used in the present study 35

4 Preserved sugar cane juice packed in LDPE pouches used in the present study 35

5 Jaggery packed in LDPE used in the present study 36

6 Jaggery packed in paper bag used in the present study 36

7 Irradiation Unit 38

8 Irradiation of sugar cane juice 38

9 Microbial analysis of the preserved products 42

10 Organoleptic Evaluation of the preserved products used in the present study 43

LIST OF APPENDIX

APPENDIX TITLE PAGE No.

A Estimation of moisture content 121

B Estimation of reducing and total sugars 122

C Estimation of ascorbic acid 124

D Estimation of carbohydrates 126

E Preparation of mineral solution 127

F Estimation of iron 128

G Estimation of calcium 130

H Estimation of phosphorus 133

I Estimation of viable bacterial count 134

J Estimation of viable yeast and mold count 135

K Score card for sugarcane juice 136

L Score card for jaggery 137

ACKNOWLEDGEMENT

I give all the praise and glory to the Lord Almighty for his love and grace as

no success is possible without his blessings.

I wish to express my grateful thanks to my beloved parents mother Mrs.

Neeta Sankhla, my father Mr. Manohar Lal Sankhla, my lovable brother Mr. Sahil

Sankhla, my cousin Mr. Rahul Gaur and all my relatives for the help and support

they have rendered in bringing the project to its relevance in a fruitful manner.

I feel a great pleasure in expressing my whole hearted sense of gratitude to

the Chairman of the Advisory Committee, Dr. (Mrs.) Anurag Chaturvedi, Associate

Dean and Professor, Department of Foods and Nutrition, College of Home Science,

Saifabad, Hyderabad for her guidance, constructive criticism, unceasing interest,

patient audience, caring nature, moral support and also for all her help in bringing

out this thesis, without whom it was impossible to complete the research project.

I wish to express my esteem towards Dr. (Mrs.) K. Aparna, Member of

Advisory Committee, Assistant Professor, Department of Foods and Nutrition, Post

Graduate and Research Centre, College of Home Science, ANGRAU,

Rajendranagar, Hyderabad, for her sustained interest, caring nature, immense help,

fruitful advice and co-operation

I wish to take this valuable opportunity to express my deep sense of gratitude,

sincere and profound thanks to Dr. K. Dhanlakshmi, Member of the Advisory

Committee, Associate Professor, Department of Microbiology, College of

Veterinary Science, Rajendranagar, Hyderabad for her sincere, able and meticulous

guidance during the entire period of this study. Her constant encouragement,

constructive suggestions have helped me throughout the thesis work.

I wish to express my esteem towards Dr. P. Yasoda Devi, Professor and

Head, Department of Foods and Nutrition, Post Graduate and Research Centre,

College of Home Science, ANGRAU, Rajendranagar, Hyderabad for her sustained

interest, fruitful advice and co-operation.

I express my sincere thanks to Dr. Uma Maheswari, Dr. Krishna Kumari,

of the Department of Foods and Nutrition, Post Graduate and Research Centre,

College of Home Science, ANGRAU, Rajendranagar, Hyderabad for their support

and advice during the course of the research period.

My thanks are also due to Dr. Sridhar, Principal Scientist, , Mrs

Padmavati, Mr Pawan, Mrs Sujatha, Ms Deepti and Ms Aparna, QC Lab, EEI

Extension for permitting me to utilize their laboratory facilities and helping me in

carrying out the analysis and I am grateful to them

It is time to surface out my overwhelming sense of affection to my friends

Anurag Shenoy, Nandini M. Arora, A. Peter Amala Sujith, Tanya Luva Swer,

Madhu, Swapnja, Thanvi, K. Priyanka, Ch. Shruti Ratna and my juniors

Niharika, Harsha, Vahini.

Distance can never be too… to make me really apart from Mirnalini, Ram,

Deepika, Keertika, Sanjiv , Shahida who are constant source of warrior rage and

retrospection for me.

I wish to convey my heartfelt thanks to the Venkatiah, Yedukondalu, Ravi,

Hari Babu, Madhavi and the rest of the non-teaching staff members of Department

of Foods and Nutrition, Post graduate and Research Centre, College of Home

Science, ANGRAU, Hyderabad for their timely and untiring help.

I am grateful to the authorities of Acharya N.G. Ranga University

(ANGRAU) for having provided the opportunity to study in the university.

Finally, I would like to thank everybody who was important to the successful

realization of thesis, as well as expressing my apology that I could not mention

personally one by one.

Date: (SNEH SANKHLA)

LIST OF ABBREVATIONS AND SYMBOLS β : Beta

@ : at the rate of

% : Percent

± : Plus-Minus Symbol

ANOVA : Analysis of variance

AOAC : Association of Analytical Chemists

cc : Cubic centimeter

CD : Critical difference

oC : Degrees centigrade

cfu : colony forming unit

et al : and others

e.g., : For example

FDA : Food and Drug Administration

Fig. : Figure

g : Gram

g/l : Grams per litre

hrs : Hours

i.e., : that is to say, in other words

kg : Kilogram

kGy : Kilo gray

KMS : Potassium metabisulphite

l : Litre

LDPE : Low Density Polyethylene

mg : Milligram(s)

min : Minute(s)

ml : Milliliter(s)

mm : millimeter

N : Normality

NaOH : Sodium hydroxide

NS : Non significant

µg : Microgram

PET : polyethylene tetrapthelate

pH : Log of H+ ion concentration

ppm : parts per million

S.Em. : Standard Error mean

Viz., namely

Author : SNEH SANKHLA ID No. : FST/2008 – 003 Title of the Work : A STUDY ON INCREASING THE SHELF LIFE

OF SUGARCANE JUICE AND JAGGERY USING HURDLE TECHNOLOGY

Degree to which it is submitted : MASTER OF SCIENCE IN FOOD SCIENCE

AND TECHNOLOGY Faculty : FACULTY OF POST GRADUATE STUDIES Major Field : FOOD SCIENCE AND TECHNOLOGY Major Advisor : Dr. (Mrs.) ANURAG CHATURVEDI University : ACHARYA N.G. RANGA AGRICULTURAL

UNIVERSITY Year of Submission : 2010

ABSTRACT

Sugarcane juice was subjected to heat and chemical treatments. Pasteurization temperature and chemical concentrations were optimized. Following treatments were given to juice viz. untreated; pasteurization at 800C for 10 min + chemical treatments (KMS @ 150ppm and citric acid @ 0.05%); pasteurization at 800C for 10 min + chemical treatments (KMS @ 150ppm and citric acid @ 0.05%) + sterilization at 800C for 20 min. All the samples were packed in glass bottles, polyethylene Tetrapthelate (PET) bottles and low density polyethylene pouches (LDPE). After packaging all the samples were subjected to irradiation at 0.25kGy, 0.5kGy and 1.0kGy. Non – irradiated samples were taken as control. The storage studies were carried out upto 90 days at room and refrigerated temperature.

Jaggery was packed in LDPE pouches and paper bags and then subjected to

irradiation at 3 kGy, 5kGy and 7kGy. Irradiated and non irradiated samples were stored at room temperature upto 90 days.

On treatment moisture content, ascorbic acid, viable bacterial count and

viable yeast and mold count were decreased significantly (P>0.05) where as no significant effect was observed on reducing and total sugars in cane juice. Irradiation also showed a similar effect except of total sugars which decreased on irradiation. Because of good barrier properties to oxygen and water vapor glass and PET bottles were found to be at par in increasing the shelf life of sugarcane juice in

comparison to LDPE pouches. Irradiation and packaging material statistically showed no significant differences on organoleptic properties of juice.

On storage, ascorbic acid and total sugars were decreased significantly

(P>0.05). Moisture content, viable bacterial count and viable yeast mold count were increased on storage at 5% significant level. The increase was more at room temperature than at low temperature. Scores for colour, taste, flavor, texture and overall acceptability were decreased with increase in storage period.

Among all the treatments pasteurization at 800C for 10 min + chemical

treatments (KMS @ 150ppm and citric acid @ 0.05%) + sterilization at 800C for 20 min was found to be best in maintain the shelf life of juice with 1.0kGy irradiation doses. Among glass bottles, PET bottles and LDPE pouches, glass and PET were found to be best in maintaining the quality of juice.

Effect of irradiation and packaging was found to be statistically non

significant (P>0.05) on reducing sugars, sucrose, viable bacterial count and viable yeast and mold count of jaggery except that of moisture content which showed an significant increase (P>0.05) on irradiation in jaggery. Irradiation at 7.0kGy dose was found to be best in maintaining the keeping quality of jaggery. Irradiation and packaging material showed no significant changes on organoleptic properties.

On storage moisture content, reducing sugars, viable bacterial count and

yeast and mold count increased significantly (P>0.05) in jaggery. Decrease in sucrose content was observed during storage. No significant changes (P>0.05) were noticed in scores for colour, taste, flavor, texture and overall acceptability during storage period. Jaggery irradiated at 7.0kGy stored in LDPE pouches was found to be best till the end of the storage period.

Therefore it has been concluded that pasteurization at 800C for 10 min with

preservatives (KMS @ 150ppm and citric acid @ 0.05%) and sterilization at 800C for 20 min along with irradiation dose 1.0kGy was found to be best combination in increasing the shelf life of cane juice.

For Jaggery irradiation dose at 7.0kGy was found to be best in increasing

the shelf life upto 90 days without having much affect on its physico-chemical, nutrional and organoleptic properties.

Hence the present study conducted is a preliminary step for preservation

of sugarcane juice and jaggery. Consumers have become more conscious about food safety therefore hurdle technology has arisen in response to number of developments and therefore provides a framework for combining a number of milder preservation techniques to achieve an enhanced level of product safety and stability.

1

Chapter I

INTRODUCTION

Sugarcane is one of the tallest member of grass family with potential to

grow upto 14 feet high under tropical conditions (Yadira et al., 2005). Sugarcane,

an important cash crop in agriculture sector shares 7% of the total value of

agriculture output and occupies only 2.5% of India’s gross cropped area. Sugarcane

provide useful raw material to various industries to produce sugar, jaggery,

khandsari and a range of agro industrial products.

Sugarcane which belongs to the genus Saccharum of the grass family has

six species namely S.officinarum, S. barberi, S.sinense, S. robustum, S. sponteneum

and S. elude of which the first three are cultivated and others are wild (Verma,

2004). Sugarcane is used to obtain juice and jaggery.

In India sugarcane is generally crushed to obtain juice which serves as a

thirst quenching drink in hot summers. Sugarcane juice is great for recharging

energy because it is rich in carbohydrate and iron. Being a nutritious product

containing natural sugars, minerals and organic acids, sugarcane juice has many

medicinal properties. It strengthens the stomach, kidneys, heart, eyes, brain and sex

organs. The juice is beneficial in fevers. Sugarcane juice is very useful in scanty

urination. It keeps the urinary flow clear and helps the kidneys to perform their

functions properly. It is also valuable in burning micturation due to high acidity,

gonorrhea, enlarged prostrate, cystitis and nephritis. For better results, it should be

mixed with lime juice, ginger juice and coconut water. Mixed with lime juice, it can

hasten recovery from jaundice. Sugarcane juice is a fattening food. It is thus an

effective remedy for thinness. Rapid gain in weight can be achieved by its regular

use (Karthikey and Samipillai, 2010).

2

Sugarcane juice contains water, non reducing sugars, reducing sugars,

organic, inorganic substances and nitrogenous bodies. In general sugarcane juice is

spoiled quickly by the presence of sugars (Krishnakumar and Devadas, 2006a).

Microorganism present in juice leads to loss of sucrose by formation of

organic acid and ethanol. Major bacteria responsible for spoilage are Leuconostoc,

Enterobacter, Flavobacteruim, Micrococcus, Lactobacillus, Actinomyces. Among

yeast and molds, Aspergillus, Cladosporium, Monilla, Penicillium, Saccharomyces,

Candidia, Pichia, Torulopsis are responsible for spoilage (Frazier and Westhoff,

2007).

It has been reported that bacteria such as Leuconostoc spp from cane field

enters inside the cane through cut ends or damaged suites and therefore reduces the

quality of milled juice by formation of dextran. This dextran further reduces the

viscosity of juice (Singh et al., 2006).

The quality of cane juice is also affected by chemical (acid) and enzymatic

inversion (Singh et al., 2006). The sugarcane plants have two kinds of invertases,

namely neutral invertase (NI) and acid invertase (AI). They are highly correlated

with sucrose and reducing sugar contents during plant growth (Siswoyoa, et al

2007). These enzymes lead to inversion of sucrose.

Jaggery being another popular product obtained from sugarcane. Jaggery is

defined as the product obtained on concentrating the sweet juices of sugarcane with

or without prior purification of juice, into a solid or semi solid state. It is also

termed as “vellum” or “bellam” in south India. It is produced in almost all parts of

India where sugarcane is grown. Gur (jaggery) is manufactured in India every year

from November to Middle of April, and is stored both for marketing and human

consumption during the remaining part of the year. Jaggery is often called the

medicinal sugar and posses nutritive properties of high order. It helps in purification

3

of blood, prevents rheumatic afflictions and bile disorders. Magnesium found in

jaggery strengthens the nervous system and potassium conserve the acid balance in

the cells and combats acids and acetones. Jaggery is rich in iron and prevents

anemia. Jaggery supplements the requirement of iron and calcium in women and

children and also increases vitality in men and helps in digestion. The

micronutrients present in jaggery have antitoxic and anticarcinogenic properties. Its

dietary intake can prevent the atmospheric pollution related toxicity and the

incidence of lung cancer (Rao et al., 2007).

A quality jaggery is golden yellow in colour, hard in texture, crystalline in

structure, sweet in taste, less in impurities and low in moisture. The quality jaggery

is influenced by the variety of cane grown, quantity of fertilizers used, quality of

irrigation water and method of processing adopted (Asokan, 2007).

The keeping quality of jaggery largely depends on the atmospheric

humidity and temperature. Jaggery is mostly spoiled during the monsoon period.

During high humidity the outer layers of jaggery absorbs moisture from the

atmosphere. This absorption of moisture always precedes other changes and set up

favorable conditions for inversion and growth of different types of bacteria and

fungi which ultimately leads to the production of alcohols, organic acid and

complex decomposition products. Due to inversion there is an increase in the

amount of invert sugar which absorbs more moisture and a vicious circle is formed.

The process goes on till the solid lumps of jaggery become soft and loose in some

cases a viscous liquid commonly known as “gur running” begins to ooze out (Roy,

1951).

Food preservation in the broad sense of the term refers to all measures taken

against any spoilage of food. Factors which are used for food preservation are

called hurdles. The microbial stability and safety of most traditional and novel

foods is based on a combination of several preservative factors which

4

microorganisms present in the food are unable to overcome. This is known as

hurdle effect. It was first introduced by Leistner in the year 1978.

The hurdle effect is of fundamental importance for the preservation of

foods, since the hurdles in a stable product control microbial spoilage, food-

poisoning, as well as desired fermentation processes. From an understanding of the

hurdle effect, hurdle technology was derived, which allows improvements in the

safety and quality of foods using deliberate and intelligent combinations of hurdles

(Leistner, 1999).

Potential hurdles for use in the preservation of foods can be divided into

physical, physicochemical, microbially derived and miscellaneous hurdle. Among

these hurdles, the most important one have been used for centuries are high

temperature, low temperature, water activity, acidity, redox potential (Eh),

competitive microorganism (e.g. lactic acid bacteria) and preservatives (e.g. nitrite,

sorbate, sulphite) (Leistner and Gorris, 1995).

Recently, about 50 additional hurdles have been used in food preservation.

These hurdles include: ultrahigh pressure, mano-thermo-sonication, photodynamic

inactivation, modified atmosphere packaging of both non-respiring and respiring

products, edible coatings, ethanol, Malliard reaction products and bacteriocins

(Ohlsson and Bengtsson, 2002).

Hurdle technology has arisen in response to number of developments and

therefore provides a framework for combining a number of milder preservation

techniques to achieve an enhanced level of product safety and stability.

5

Both sugarcane juice and jaggery are highly perishable commodities. So

there is an urgent need to preserve them. Therefore the recent study was undertaken

to increase the shelf life of sugarcane juice and jaggery using hurdle technology

with following objectives:

Specific objectives:

1. To preserve sugarcane juice and jaggery using hurdle technology.

2. To perform shelf life studies using a suitable packaging material (paper based

material and polyethene).

3. To perform nutritional, microbiological and sensory evaluation of juice and

jaggery before, during and after storage.

6

Chapter II

REVIEW OF LITERATURE

Sugarcane juice is one of the delicious drink that enjoys a wide popularity in

view of its pleasing taste, refreshing tingle and availability during the greater part of

the year throughout the country. The main problem associated with fresh sugarcane

juice is its short life and heat sensitivity of its flavor. Therefore the drink is mostly

sold – fresh by roadsides and small eateries. Therefore, most of the attempts to

preserve the sugarcane juice have been focusing on the use of refrigeration, heat

treatment and preservatives.

On other hand jaggery has the major problem with storage. From olden days

different storage materials have been used to store jaggery like earthen pots,

wooden bins etc. but such storage conditions effect quality of jaggery.

Hence to preserve and increase the shelf life of sugarcane juice and jaggery

new concept of hurdle technology was adopted.

The literature pertaining to present study is presented under following

sections.

2.1 NUTRITIONAL COMPOSITION

2.1.1 Nutritional composition of sugarcane juice

Sugarcane (Saccharum officinarum L.) is one of the most important cash

crops in the world. India is the world’s second largest producer of sugarcane next to

Brazil. Presently in India about 4 million hectares of land is under cultivation of

sugarcane with average yield of 70 tonnes per hectare (Krishnakumar and Devadas,

2006b).

7

Sugarcane juice is commonly used as delicious drink in both urban and rural

areas. Its composition may vary according to cane variety, geographical locations,

cultural practices, maturity at harvest and also mechanical treatment during

harvesting and transportation. The principal constituent of cane juice are sugars,

salts, organic acids and other organic non- sugars such as proteins (Yadira et al.,

2005). The composition of sugarcane juice is presented in Table 2.1.

Table 2.1 - Nutritive Value of Sugarcane Juice per 100ml

COMPOSITION AMOUNT Water 90.2% Total carbohydrates 9.1g Calcium 10 mg Iron 1.1 mg Thiamine 0.02 mg Riboflavin 0.02 mg Vitamin C 5 mg Calorific value 36 Kcal (Source: Swaminathan, 1991)

2.1.1.1 Carbohydrates

The most common carbohydrates consist of the monosaccharides, glucose

and fructose and the disaccharide, sucrose. Oligosaccharides and polysaccharides

may be present depending on the age of the cane when harvested. Polysaccharides

are condensed monosaccharides, which occurs in the form of starch, gums and

dextran in cane juice. Formation of dextran is associated with infection of

damaged, harvested cane by Leuconostoc bacteria (Walford,1996).

Table 2.2 - Carbohydrate Composition of sugarcane juice

Carbohydrate Concentration Monosaccharides (%) Glucose

Fructose 0.26-0.33 0.26-0.33

Disaccharides (%) Sucrose 9.6-10.9 Oligosaccharides (% ) 1-kestose

6-kestose Neo-kestose

0.26-0.33 0.03-0.5 0.01-0.4

Polysaccharides (% ) 0.3-1.3 (Source: Walford,1996)

8

2.1.1.2 Inorganic salts

The inorganic components of sugarcane juice consist of water and elements

dissolved in it as ions, and parts of organic compounds. Phosphates, magnesium and

silica are the most important from clarification viewpoint as these are partially

removed. The other ions remain in solution and become concentrated with

processing. The mineral content of the juice depends on cane variety and soil

(Walford, 1996).

Table 2.3 - Mineral Concentration in sugarcane juice

Constituents Concentration (%)

Cations

Potassium Sodium Calcium Magnesium Iron Aluminium Copper Zinc Manganese Cobalt Silicon

0.77-1.31 0.01-0.04 0.24-0.48 0.10-0.39 0.006-0.04 0.005-0.17 0.002-0.003 0.003-0.012 0.007 0.00007 0.016-0.101

Anions Chloride Phosphate Sulphate

0.16-0.27 0.14-0.40 0.17-0.52

(Source: Walford, 1996)

2.2.3 Organic acids

The organic acid composition of juice may be divided into the non-

nitrogenous acids (Table 4) and the amino (nitrogenous) acids (Table 5). Although

comprising of a small fraction, they are responsible for the natural pH of the juice

(5.2 – 5.4) as well as its buffering capacity (Walford, 1996).

9

Table 2.4 - Non-nitrogenous organic acids present in cane juice

Acids Concentration (ppm) Natural Oxalic acid

Citric acid Tartaric acid Malic acid Aconitic acid Succinic acid Glycoloic acid

40-200 900-1,800 10-180 1,200-1,800 5000-8000 100-200 Trace-150

Formed during processing

Lactic acid Acetic acid

250-670 200-300

(Source: Walford, 1996)

Table 2.5 -Amino acid composition of cane juice

Compound Free % Dry solids Amides Asparagine

Glutamine 0.71 0.19

- -

Amino acids

Aspartic Glutamic Alanine Valine Aminobutyric Threonine Isoleucine Glycine All others

0.11 0.05 0.06 0.03 0.03 0.02 0.01 <0.01 Trace

0.06 0.08 0.05 0.04 0.03 0.04 0.03 0.04 <0.03

(Source: Walford, 1996)

2.2.4 Other constituents

Other minor constituents in cane juice consist of waxes, fats and

phosphatides which are extracted from the rind and leaves of the cane and can

constitute approximately 0.1%. They are normally removed during clarification.

Coloring matter in juice consists of a variety of organic compounds including

chlorophylls, carotene, flavonoids and polyphenols (Walford, 1996).

It has also been reported that sugarcane juice exhibit antioxidant activity and

has the ability to scavenge free radicals, reduce iron complex and inhibit lipid

peroxidation (Kadam et al., 2008).

10

2.1.2. Nutritional composition of jaggery

Jaggery is basically comprised of 60-85% sucrose, 5-15% glucose and

fructose along with 0.4% protein, 0.1% fat and 0.6-1.0% of minerals ( 8 mg of

calcium, 4 mg of phosphorus, 114 mg of iron/100gm of jaggery). 100 gm of jaggery

gives 383Kcal of energy. It has also been found to contain traces of vitamin, amino

acids and antioxidant. (Asokan, 2007).

Sugars, minerals and colloids are main constituents of jaggery that govern

the physico-chemical characteristics. Good jaggery contains a high amount of

sucrose, lime, phosphate, and less glucose, ash, chloride and organic non-sugars.

The presence of total non-sugars and organic non-sugars decreases the quality of

jaggery (gur) (Thangavelu, 2007).

Quality jaggery is graded on the basis of colour, texture and taste. Normally

jaggery (gur) with light colour is preferred for consumption. The inherent sugarcane

juice characteristics, iron crushers, boiling pans and the processing of juice are the

major sources for colour development in jaggery. Anthocyanin and saccharetin are

two organic non-sugars which react with iron salts present in juice or by contact

with crusher and pan, are responsible for dark colored jaggery (Thangavelu, 2008).

Texture and hardness of jaggery are inter-related. Soft jaggery would have a

soft texture and vice-versa. Generally granular texture is preferred for table purpose,

while amorphous texture for cooking or making sweetmeat products. The sweet

taste in jaggery is due to the presence of fructose and dextrose (Patil and Adsule,

1998).

11

2.2 SPOILAGE OF SUGARCANE JUICE

Sugarcane juice is highly fermentable as cane juice is a rich medium which

contains about 15-18% sucrose, 0.5%reducing sugars and adequate amount of

organic nitrogen and mineral salts for microbial growth. Its pH ranges from 5.0-5.5

making it selective for acidophilic microorganism especially yeast and lactic acid

bacteria. Large population of yeast favors the ethanol production at the expense of

sucrose. The microbial contamination of the juice is usually extremely high, typical

viable counts being 108-109 cells/ml of juice. The major loss of sugar occurs due to

inversion of sucrose in raw sugar cane juice and other types of degradation of the

juice caused by bacterial activities, enzymes and other biological factors (Solomon,

2009).

Moreover spoilage depends on the type of cane used for juice extraction.

The rate at which harvested cane deteriorates is influenced primarily by

temperature, humidity, cane variety and the state of the stalk (Lionnet, 1986).

Invertases (β-D-fructofuranosidase, E.C. 3.2.1.26) are the key enzymes

involved in sucrose metabolism in sugarcane plants. The sugarcane plants have two

kinds of invertases, namely neutral invertase (NI) and acid invertase (AI).They are

highly correlated with sucrose and reducing sugar contents during plant growth

(Siswoyoa et al., 2007). A positive correlation has been established between acid

invertase activity and stem elongation rate in sugarcane. These enzymes are

responsible for inversion in cane and milled juice (Sachdeva et al., 2003).

According to Solomon (2009) change in invertase activity in harvested cane is also

associated with loss of moisture from cane.

Sugarcane juice is also spoiled by bacteria such as, Leuconostoc,

Enterobacter, Flavobacteruim, Micrococcus, Lactobacillus, Actinomyces. Among

yeast and molds, Aspergillus, Cladosporium, Monilla, Penicillium, Saccharomyces,

Candidia, Pichia, Torulopsis are responsible for spoilage (Frazier and Westhoff,

2007).

12

It has been reported that bacteria such as Leuconostoc spp from cane field

enters inside the cane through cut ends or damaged suites and reduces the quality of

milled juice. The Leuconostoc bacteria have the ability to synthesize alpha – glucan

polysaccharide (dextran) from sucrose through an extracellular enzyme called

dextran sucrose. This dextran further increases the viscosity of the juice (Singh et

al., 2006)

Dextransucrase Sucrose + Water (glucose) n + fructose Leuconostoc 2.3 PROCESSING

2.3.1. Processing of Sugarcane Juice

Rapid fermentation of sugarcane juice is the main hurdle faced in processing

and preservation of juice.

Sodium benzoate and aqueous ammonia have been used to stop the

fermentation of sugarcane juice. Sodium benzoate at a concentration of 0.05%was

sufficient to stop fermentation for 2 – 3 days and 0.1% was enough to preserve the

juice for 6days. On the other hand aqueous ammonia at a concentration of 0.32%

preserved the juice for 2 days and 1.28% upto 6 days (Bobadilla and Preston, 1981).

A scheme for producing bottled cane juice was developed by Kaur et al.

(1995) which consists of pasteurizing the extracted juice for 10 min at 80 degrees C,

adding K2S2O5 equivalent to 70 ppm. SO2, hot bottling, sterilizing for 30 min at

1000C and cooling for storage. To improve the flavour, the initial juice was blended

with 0.3% lemon juice and 0.1% ginger juice. Simple pasteurization and

refrigerated storage (8-10 degrees) gave a shelf-life of only 2 days, where as the

pasteurization, adding K2S2O5 , hot bottling and sterilization maintained the shelf

life for more than 24 weeks. Also it was noticed that Leuconostoc mesenteroides

activity was absent from both plain and treated juices.

13

Sugarcane juice beverage samples were prepared by pasteurizing the

sugarcane juice at 70°C for 10 minutes and adding citric acid (40 mg/100 ml),

ascorbic acid (40 mg/100 ml) and potassium metabisulphite (150 ppm). Samples of

sugarcane juice beverage were stored at room (30±5°C) and refrigeration (4±2°C)

temperature in pre-sterilized glass bottles for 90 days. The pH, total soluble solids

and total sugars decreased, whereas, titratable acidity and reducing sugars increased

significantly (P<0.01) during storage. (Chauhan et al., 2002).

Pushpa et al. (2002) developed a process for the preparation of sugarcane

juice concentrate using citric acid alone and in combination with sodium benzoate.

Treated samples were packed in glass bottles. It was also noticed that concentrate

when treated with citric acid (0.5%) and sodium benzoate (500 ppm) in

combination showed the best result in terms of appearance, clarity, colour, flavour,

taste and shelf life was increased upto 8 months.

Madsen et al. (2005) reported work on preservation of sugarcane juice using

mixed dithiocarbamates. The study focused on use of mixtures containing

methyldithiocarbamic acid sodium (Vapam) and ethylenebis (dithiocarbamic acid)

disodium salt (Nabam) on sugarcane juice. Biocides were applied at levels ranging

from 5 to 20 mg/kg. It was shown that biocide applied at levels greater than 5

mg/kg could preserve sugar cane juice.

A wine like beverage was prepared by Yadira et al. (2005) from sugarcane

juice using two strains of yeasts (Saccharomyces cerevisiae and Saccharomyces

cerevisiae var. ellipsoideus) . Apart from this two additional products were obtained

after adding passion fruit juice and roselle (Hibiscus sabdarifa Linn) concentrates.

The fruit flavoured wines were significantly preferred over the plain product.

Bosse et al. (2006) preserved sugarcane juice by heating it to a different

temperature (75, 85 and 950C) with addition of potassium metabisulphite and citric

14

acid. A decrease on pH was observed at elevated time and temperature of

pasteurization. Also reducing sugars showed an upward trend as the temperature of

pasteurization increased and sucrose levels decreased.

Mao et al. (2007) worked on maintaining the quality of sugarcane juice with

blanching and ascorbic acid. The study showed the physiochemical changes in fresh

sugarcane juice stored at 10˚C. It was seen that blanching of stems before squeezing

the juice and use of ascorbic acid (0.1%) improved the quality of sugarcane juice

by preventing degreening and/or browning, and reduced activities of PPO

(polyphenol oxidase) and SNI (sugarcane neutral invertase) in fresh sugarcane

juice.Addition of ascorbic acid appeared to be more effective than blanching.

2.3.2 Sugarcane juice blends

The processing method for preservation of sugarcane juice blends with

different fruit juices was standardized by Sujatha et al. (2007). Addition of

preservative (potassium metabisulphite 125 ppm) was found to be the best when

compared to sodium benzoate. The sugarcane juice blended with grape juice and

pineapple juice was highly acceptable and could be stored for a period of 120 days

in glass bottles when compared to other combinations and was found to be the best

in their keeping quality and consumer acceptability.

Pure sugarcane juice and sugarcane juice mixed with fresh lemon and

pineapple juice was subjected to a heat treatment (750C/25 min) and /or gamma

radiation (2.5 kGy) and stored in high density polyethylene bottles. Processing of

the sugarcane juice reduced the microorganism load without significantly altering

the physicochemical composition, aroma and flavor of the beverages in comparison

with the control (Oliveira and Garcia, 2007).

A ready to serve beverage (RTS) was developed using sugarcane juice and

pineapple juice blend in 2:8, 4:6 and 8:2 ratio. Sodium benzoate (100 ppm and 125

15

ppm) and potassium metabisulphite (120 ppm) were used as preservatives. Results

obtained showed that the acidity, optical density and TSS increased with increase in

the sugarcane juice content in the blend as well as the storage period (Kumar,

2009).

2.3.3. Processing of other fruit juices

Mango juice was analyzed after bottling and during storage for 2 and 4

months, in order to follow the changes in aroma constituents which have an adverse

influence on the juice quality. Heat processing at 85°C/10 min caused the reduction

of all volatile fractions and, leads to the formation some compounds which were

attributable to degradation reactions. Storage of bottled mango juice at room

temperature resulted in the appearance of ethyl fatty acids and seline-11-ene-4-ol,

which affected the flavor of mango juice (El-Nemar, 1988).

Sweetened mango juices were processed, bottled and stored at 25 °C for

12 weeks. The titrable acidity, pH, total solids, ash, soluble solids and ascorbic acid

contents were evaluated immediately after processing and subsequently at 2-week

intervals. The quality attributes of the sweetened mango juices decreased during

storage. After 12 weeks of storage, the percentage ascorbic acid loss of sweetened

Julie and Ogbomoso mango juices was 16.25 and 16.67%, respectively. Browning

index increased during storage. (Falade et al., 2004).

Orange juice was stored at refrigerated temperature without preservative and

at room temperature with preservative for a period of 4 weeks. At refrigerated

temperature there was decrease in pH and titrable acidity. But there was no change

in pH and titrable acidity (TA) at room temperature. The storage of orange juice

brought about a loss of 5-8% vitamin C at refrigerated and room temperatures after

4 weeks (Goyle and Ojha, 1998).

16

The chemical, enzymatic changes and shelf life of pasteurized orange juice

packed in polyethylene teraphthalate bottles stored at 40C were evaluated. Two

batches of orange juice samples were pasteurized at 720 C for 16 seconds and at

900C for 40 seconds. The orange juice samples were evaluated periodically for

relative density, soluble solids (degrees Brix), titrable acidity, pH, suspended solids

(pulp), ascorbic acid, colour, and pectin esterase activity. The juice samples

exhibited good stability and no statistical difference was observed among the

treatments, except for colour (turbidity) that increased with longer storage time.

(Correo et al., 2003).

A study was done by Zanoni, et al (2005) to examine the quality and shelf-

life of freshly squeezed, unpasteurized blonde and blood orange juice from organic

farming methods. Thermal treatment had an effect on nutritional and sensory

quality of blonde orange juice. Shelf-life studies revealed that unpasteurized juices

could be stored at approximately 100C for 10 days without significant growth of

spoilage microorganisms. However decrease in ascorbic acid and anthocyanin

content was observed during storage.

Litchi juice was extracted from ripe litchi fruits. The extracted juice was

subjected to different treatments: T1 = heating at 850 C + citric acid (1%) + KMS

(500 ppm); T2 = citric acid (1%) + KMS (500 ppm); T3 = heating at 85 degrees C +

citric acid (1%) + ascorbic acid (0.01%) + KMS (500 ppm); and T4 = citric acid

(1%) + ascorbic acid (0.01%) + KMS (500 ppm). The processed juice samples were

kept in glass bottles sealed with crown corks and stored for 12 months at 11-360C

(room temperature) and at 5-80C (low temperature). Results showed that bottled

litchi juice maintained acceptable colour and quality for up to 12 months when

stored at low temperature and only up to 6 months for T1 and T3 samples stored at

room temperature (Alex et al., 2003).

17

A study was done to develop a low cost method of lime juice preservation.

Pasteurized (770C for 60 seconds) and non-pasteurized juice were treated with

different levels of potassium metabisulfite (500 ppm, 1000 ppm, 1500 ppm and

2000 ppm) and stored in glass bottles at room temperature for 3 months. Results

obtained showed that total soluble solids increased during storage while sulfur

dioxide (SO2) and ascorbic acid contents gradually decreased. Non-pasteurized

juice was found to be the most acceptable in terms of organoleptic evaluation. It

was found that lime juice could be preserved for a period of about 10 weeks

without any undesirable changes by using SO2 at an initial level of 500 ppm

(Ekanayake et al., 2004).

Shelf life of Passion Fruit Juice was increased using sugar, benzoic acid,

citric acid and a combination of citric and benzoic acid. The result showed that 30%

benzoic acid was able to preserve the juice for one month and was found to be the

best method .The juice with 4% sugar was spoiled after three days, while that of

4% citric acid could be stored for one week and some days. The combination of 3%

benzoic acid and 4% citric acid increased the shelf life upto two to three weeks.

(Akpan and Kovo, 2005).

A study was done to determine the most suitable combination of

preservative (sodium benzoate) and pasteurization levels for the preservation of

pomegranate juice at room temperature. After extraction, the juice was submitted to

various levels of pasteurization (i.e., no pasteurization, 60°C, 70°C and 80°C) and

sodium benzoate treatment (i.e., 0, 400, 500 and 600 ppm). In juice samples treated

with both pasteurization at 70°C and sodium benzoate at 500 ppm minimum

changes were observed in all physicochemical parameters (Suryawanshi et al.,

2008).

18

Grape juice was studied for one month at room temperature, after adding

sodium benzoate and potassium sorbate (treatment T1: 0.1% sodium benzoate, T2:

0.2% potassium sorbate, T3: 0.1% sodium benzoate + 0.2% potassium sorbate, T4:

control). Stability of ascorbic acid was found to be highest in T3, followed by T1,

T2, and T4. Acidity and total soluble solids increased during storage. T1 obtained

maximum score (8.0) for overall acceptability. T1 was found to be better for

preserving nutritive and sensory values of the grape juice (Alam et al., 2009).

2.4. SPOILAGE OF JAGGERY

By and large, gur (jaggery) is manufactured in India every year from

November to Middle of April, and is stored both for marketing and human

consumption during the remaining part of the year. Jaggery is mostly spoiled during

the monsoon period because of invert sugars and mineral salts, being hygroscopic,

which absorb moisture when ambient humidity is generally high. In other words,

moisture is the main culprit in the deterioration of jaggery quality. Due to

continuous inversion of sucrose by microbes, more invert sugars are formed which

absorbs more moisture and this way a noxious circle is formed. The process

continues till gur becomes soft and loose. At this time, several fungi develop,

particularly molds (Aspergilla and Peniciliia) and members of the family

Mucroceae (Ghosh et al., 1998)

Deterioration of jaggery can be catalouged into four groups, as follows:

1. Physical Deterioration: This is the most common type which is due to the

darkening of colour. There is also loss of form (shape) through

disintegration. Occasionally, the taste is also adversely affected. (Ghosh et

al., 1998).

2. Chemical Deterioration: This is mostly in the form of inversion and

discoloration. In fact these changes affect the physical characteristics like

colour, and shape. (Ghosh et al., 1998).

19

3. Biological Deterioration: It is brought about insects, particularly ants. Ants

feed profusely on gur, make tunnels and multiple profusely in these. (Ghosh

et al., 1998).

4. Microbial Deterioration: It has been estimated that about 10% of the

jaggery is lost every year during storage due to dryage and deterioration by

microbes. The main causes of jaggery deterioration had been attributed to

three factors, namely hygroscopic nature of gur, presence of abundant

sucrose and high atmospheric humidity. Absorption of moisture is a

prerequisite for microbial deterioration as it creates congenial conditions for

the development of different types of micro organism, viz bacteria,

actenomycetes and fungi. The activity of these tiny little organism results in

the evolution of gases, formation of alcohols, organism acids and complex

decomposition products besides loss in weight. Because of these changes,

gur becomes unfit for human consumption (Ghosh et al., 1998).

2.4.1. Deterioration of jaggery by bacteria

In humid regions of India, storage of gur is really a serious problem and the

stockist have to suffer considerable loss of the material. Because jaggery is a

hygroscopic substance, its surface quickly absorbs moisture and becomes soft and

sticky. At high humidity, the jaggery liquefies completely. The activity of bacteria

starts soon after the surface becomes wet. Both spore forming and non spore

forming bacteria have been isolated from jaggery samples obtained after the

monsoon period. It has been found that maximum numbers of bacteria were found

on the surface (0.6mm) of gur (jaggery) at moisture level of 10-15%. (Ghosh et al.,

1998).

Farooque (1957) investigated bacterial population in different layers of

jaggery blocks. His findings indicated that (1) surface layer of jaggery block

(0.6cm) had the maximum bacterial population, then falling sharply upto a depth of

1.8cm and beyond this there was no bacterial population, (2) at 300C, bacterial

20

population increased with moisture level upto 10% beyond which there was a fall,

(3) critical maximum and minimum levels of moisture in jaggery where bacteria

cease to grow at 300C were 20% and 33%, respectively, and (4) under storage

conditions , the optimum moisture levels for the proliferation of bacteria were

between 3 and 6%.

2.4.2. Deterioration of jaggery by actinomycetes

Actinomycetes, commonly known as ray fungi have certain characters

common to both bacteria and fungi but have distinct characters to delimit them into

separate category. On agar plates these can be conviently distinguished from

bacteria. Unlike slimy bacterial colonies, these form tuft and slow growing colonies

sticking firmly to agar surfaces. Under microscope, they display slender unicellular

branched mycelia, forming sexual spores for propagation. Actinomycetes

proliferate quickly from pH 6.5 to 8.0 and their number declines at pH 5.0. The

common genera of actinomycetes are Streptomyces, Nacardia and

Micromonospora. Of these, species of Streptomyces always outnumber other forms.

(Ghosh et al., 1998).

2.4.3. Deterioration of jaggery by fungi

Fungi are cosmopolitan in distribution. These are abundantly present in soil,

water and air. Fungal propagules, by and large, are deposited on jaggery samples

both during drying, transshipment and storage. All environmental factors that

influence the distribution and proliferation of bacteria and actinomycetes also

influence the buildup of fungal flora. Fungi generally prefer acidic medium. As the

pH of the jaggery is generally in the range of 5.5 to 6.5, it becomes an ideal

substrate for their growth and reproduction. The following fungi are generally

isolated from gur: Absidia, Alternaria, Aspergilli, Cladosporium, Curvularia,

Cylindrospora, Fusarium, Monilia, Mucor, Penicilium, Rhizopus, Spicaria etc.

(Ghosh et al., 1998).

21

2.5. STORAGE STUDIES OF JAGGERY

Although the main culprit for deterioration is moisture, different storage

conditions also affect jaggery quality apart from moisture.

In a study by Uppal et al.(2002) jaggery from different sugarcane varieties

"CoJ 82", "CoJ 85", "CoJ 86", "CoJ 87" and 'CoP 211" was prepared. Fresh jaggery

was kept open at ambient temperature for 0, 30, 75, 110 days and was stored in

closed glass containers at low temperature (7-9°C) and at ambient temperature. The

results showed that storing jaggery dry at ambient temperature for 75 days,

followed by its transfer to tightly closed glass containers and kept at low

temperature was the best method for preservation of jaggery

Different storage periods were tested to evaluate the shelf life of jaggery

under low temperature conditions (7-9°C) by Uppal, (2002). With increasing

storage time, a decrease in the quality of jaggery was observed. However, microbial

growth during storage was inhibited up to 2 years and 8 months of storage. After

this length of storage, changes in some physicochemical parameters were noted, but

storage of jaggery up to one year and 8 months was very safe, with no changes in

jaggery quality.

A study was conducted to determine the suitable storage method for jaggery

by Uppal, (2004). The quality of stored jaggery was much better when preserved at

controlled low temperature (7-9°C) than ambient temperature. There was no

significant difference in the quality of jaggery stored in glass containers and

polyethylene bags at controlled temperature, showing that both storage systems are

equally good. However, at ambient temperature, the glass container was better than

polyethylene bag.

Alkathene + hessian cloth was used for wrapping jaggery (gur) and kept in

cold as well as in ordinary storage. Alkathene bags and airtight drums were found to

22

preserve jaggery (gur) without much deterioration for a long time. Jaggery (Gur)

blocks stitched in gunny and then embedded in ash remained intact. Gunny bags

lined with varnished paper or gunny bags embedded in wheat straw gave only

partial protection to jaggery (gur) from absorbing moisture. Earthen pitchers proved

to be improper storage material for jaggery (gur) (Thangavelu, 2006).

Mandal et al, (2006) stored the jaggery in the packaging materials such as

earthen pot with lid, painted earthen pot with lid, canister with lid, glass jar with

screw cap, PET jars with screw cap, heat sealed LDPE in month of May. Among

the six packaging materials LDPE was found to be the best material for storage of

jaggery during monsoon as it helped in preventing ingress of moisture, inversion of

sugar and showed the least fall of pH in comparison to other packaging material.

Next suited ones are glass jars followed by PET, canister and painted earthen pot.

Earthen pots found to be unsuitable for storing jaggery during monsoon season.

Experiments were carried out during May - December, by Mandal et al.,

(2007a) to evaluate the effect of initial moisture content of sugarcane jaggery on its

keeping quality while stored in heat-sealed low density polyethylene (LDPE)

packets during the rainy season. Data showed that with the moisture content of 7 to

27% sugarcane jaggery could only be kept in excellent condition for 3 months in

LDPE packets from May until July. Jaggery with initial moisture content of up to

16.77% remained in excellent condition until August, while that with initial

moisture content of 12.65% remained until September. The taste of jaggery with

initial moisture content of 16.77% remained unchanged until October to December.

Experiments were conducted where semi-solid jaggery was treated by

sulphur dioxide (at the rate of 40, 70, 100 ppm), sodium benzoate (at the rate of

200,400,600 ppm) and sorbic acid (at the rate of 50, 100, 150 ppm). After

treatment, samples were stored in edible canister. It was concluded that 100ppm

sorbic acid/70ppm SO2 was found to maintain the keeping quality of jaggery during

monsoon period whereas sodium benzoate was found to be ineffective in preserving

jaggery (Mandal et al., 2007b).

23

An investigation was carried out to assess the status of jaggery storage at

house hold and jaggery making units. Six forms of jaggery were stored in air tight

plastic containers and LDPE covers for a period of five months. All the respondents

used different containers for storage of jaggery on small scale. Majority (48%) of

respondents stored jaggery in aluminum and steel boxes followed by plastic boxes

(33%), sugarcane trash (10%), earthen pots (5%) and polythene bags (4%) and the

period of storage ranged from one week to six months (Usha et al., 2009).

2.6 HURDLE TECHNOLOGY

Hurdle technology is used in industrialized as well as in developing

countries for the gentle and effective preservation of foods. Previously hurdle

technology, i.e., a combination of preservation methods, was used empirically

without much knowledge of the governing principles. Since about 20 years the

intelligent application of hurdle technology became more prevalent, because the

principles of major preservative factors for foods (e.g., temperature, pH, Aw, Eh,

competitive flora), and their interactions, became better known (Leistner, 2000).

Hurdle technology was first introduced by Leistener in the year 1958 and

was derived from hurdle effect. This concept is also referred to as combined

methods, combined processes, combination preservation, or combination

techniques. At present, the term hurdle technology is most often used.

Preservation of pineapple, papaya and mango chunks was done using

hurdle technology (Vijayanand, 2001). Mango and pineapple chunks were

blanched in 20° brix and 40° brix sucrose syrup along with 0.2% citric acid at

85°C for 5 min. They were then dipped in 20° brix sucrose syrup with 0.2% citric

acid, 340 mg potassium metabisulphite/kg and 413mg sodium benzoate /kg for 8

hours at ambient temperature in polypropylene pouches. Similarly papaya chunks

24

were also blanched in 40°C brix syrup with 0.6% citric acid at 85°C for 5 min.

and dipped in 40°brix syrup at 27°C with 0.6% citric acid, 680 mg potassium

metabisulphite/kg and 826 mg sodium benzoate /kg for 8 hr. Mango and

pineapple chunks were stored at 2 and 27°C for 60 days .Mango and pineapple

chunks showed acceptable microbial and sensory qualities upto 30 days at 27°C

and 60 days at 2°C. Papaya chunks treated with increased level of preservatives

exhibited good storage stability upto 90 days at 2°C and 27°C.

The effects of combining techniques such as addition of sorbic acid,

modification of water activity (aw), reduction of pH, modification of the packaging

atmosphere and control of the storage temperature on the microbiological shelf life

of avocado purée were evaluated during four months of storage. Results show that

the addition of 300 mg/kg of sorbic acid can extend the shelf life upto four months.

Vacuum packaging as well as storage at 4°C was also found to have a significant

influence over the control of yeast and mould populations and could preserve

avocado purées during 112 days without addition of antimicrobial. The addition of

maltose reduced water activity to 0.96 resulted in slightly more stable purées

(Robert et al., 2004).

Mango cubes were preserved using following hurdles: water activity

reduction, pH reduction, and chemical preservation. The cubes were osmotically

dehydrated in a 65.5°brix sucrose solution along with 2% citric acid and 0.2%

potassium sorbate, during two hours and packed in low-density polyethylene bags

and were stored at room temperature for three months. The combination of hurdles

on the final product was not effective to make it shelf stable, since the count of

yeasts and molds increased. The cubes underwent pH reduction and color loss

during storage. Furthermore, the acceptance of the product, as well as mango

flavors intensity decrease significantly with storage time (Azeredo et al., 2005).

25

The effect of sodium bisulfite, ascorbic acid, and salt as ingredients of

syrups on the colour of jack fruit bulb was studied for 120 days using hurdle

technology. Jack fruit syrup was stored in glass jars. On evaluation, sodium

bisulfite, ascorbic acid and salt showed positive effects on the colour stability of

jack fruit bulbs during storage (Ulloa et al., 2007).

2.7 FOOD IRRADIATION

Food irradiation is a process of using ionizing radiation or ionizing energy

to treat foods, either packaged or in bulk form. It is a new promising new food

safety technology that can eliminate disease causing germs from foods. The main

sources of ionizing radiations are radioisotopes of cobalt or cesium, electron

accelerators or X- rays (Kad et al., 2005).

Early in the 1920’s a French scientist discovered that irradiation

technology could be used to preserve food. In 1963, FDA approved irradiation of

wheat and wheat flour for insect control. In 1964 additional approval was given to

inhibit the development of sprouts in white potatoes. In 1983, approval was

granted to kill insects and control microorganism in a specific list of herbs, spices

and vegetable seasonings (Makhal and Kanawjia, 2004).

The treatment received by the food product is characterized by the

irradiation dose, which is the quantity of energy absorbed by the food while it is

exposed to the irradiation field. The international unit of measurement is the Gray

(Gy). 1000 Gray is equal to one kilo Gray (kGy). One Gray represents one joule of

energy absorbed per kilogram of irradiated product. One Gy is equivalent to 100

rad (radiation absorbed dose) (Brennan, 2006).

26

The radiation dose varies with the type of food and desired action. FDA has

approved treatment levels as followed.

Low dose: Up to 1kGy designed to control insects in grains, inhibit sprouting in

white potatoes and decay and control of insects in fruits and vegetables.

Medium doses: 1 to 10 kGy designed to delay mould growth on strawberries and

other fruits.

High doses: Greater than 10 kGy designed to kill microorganisms and insects in

spices and to commercially sterilize foods, destroying all microbes of public health

concern.

Food irradiation is also called as cold sterilization. There is little or no

change in the physical appearance of irradiated foods as they do not undergo the

changes in texture and /or colour as food preserved by heat pasteurization and

canning or freezing (Bindra, 1997).

Paul (1997) stated that enzymes present in raw foods are not inactivated by

irradiation. Even in radiation sterilized foods using very high doses of 45 kGy

enzymes are active and therefore to inactivate these enzymes a mild heat treatment

is necessary prior to irradiation.

The macro nutrient like carbohydrates, lipids, proteins and amino acids

undergo minimal changes as a result of irradiation, although effect on vitamin

levels varies from food to food. Of the water soluble vitamins, thiamine,

pyridoxine and vitamin C are more susceptible than riboflavin, niacin or vitamin

B12. At the low doses used for fruits, vegetables and grains the losses are in the

range of 10 to 15%. Fat soluble vitamins A, D, E and K are stable in low doses

irradiated foods (Paul, 1997).

27

2.7.1 Effect of irradiation on fruit juices

Granny Smith apples, Valencia oranges, and Pearlette grapes grown in

Australia were irradiated at 0, 75, 300 and 600 Gy. Following irradiation, juice was

extracted. Irradiation treatment significantly (p<0.05) decreased yield of apple juice

(by 6.3% w/w at 600 Gy) and grape juice (by 4.8% w/w at 600 Gy) but did not

significantly (p>0.05) affect yield of orange juice. Acceptability significantly

(p<0.05) decreased in orange juice after 600 Gy treatment. Other changes in quality

and composition were minimal (Mitchell et al., 1991).

Effect of gamma irradiation (0-10 kGy) on the stability of anthocyanins and

inhibition of microbial growth in pomegranate juice was studied. Results indicated

that the irradiation at all applied doses, significantly reduced total and individual

anthocyanins. Moreover, irradiation with higher dosages (3.5-10 kGy) had

undesirable effect on the total content of anthocyanins. However, irradiation at 2.0

kGy had effectively diminished the total bacteria and fungi count and retarded

microbial growth during storage. Dosage higher than 2.0 kGy adversely affected the

anthocyanin content of juice (Alighourchi et al., 2008).

Tamarind juice was irradiated at 0, 1, 3 and 5 kGy at room temperature.

Microbiological assay of the fresh and stored ready-to-use tamarind juice showed

better quality after gamma irradiation. Antioxidant ability and total phenolic

contents, showed significant increase after irradiation. Contents of glucose and

fructose also showed minimal alterations both in the fresh and stored samples.

There was a significant improvement in the Hunter color value in both the fresh and

stored tamarind juice (Lee, 2009).

2.8 PACKAGING

A packaging study of orange juice aseptically packaged in bottles using

different materials and filling procedures was conducted to determine their

influence on the evolution of juice quality and shelf life. Glass, multilayer PET

28

(polyethylene terephthalate) and monolayer PET bottles were used. Monolayer

PET showed the lowest retention of ascorbic acid during storage and good shelf life

compared with multilayer PET and glass (Chumillas et al., 2007).

Microbial changes of sugarcane juice stored at different packaging materials

were studied. Sugarcane juice treated with sodium benzoate at 100 and 125 ppm

level was packed in three different packaging materials namely polyethylene (400

gauge), polypropylene (350 gauge) and glass bottles. Result obtained showed that

the increase of bacteria (2.57 X 106cfu ), yeast (4.39X 104 cfu) and fungi ( 3.0 X

103) was less in the glass bottles as compared to other packaging material after

storage for 60 days at 125ppm at 50C (Krishnakumar and Devadas, 2006a).

Mango juices were extracted from Ogbomoso variety and were packaged in

polyethylene films, PET bottles and transparent glass bottles and stored at 6°C,

26°C and 34°C respectively. Percentage ascorbic acid loss, browning index,

titratable acidity, pH and soluble solids were evaluated at 2-week intervals for

8 weeks. Percentage ascorbic acid loss, non-enzymatic browning and titratable

acidity increased with storage time in all packaging materials. Higher percentage

ascorbic acid loss, browning index and titratable acidity occurred in juices packaged

in polyethylene film, than in PET and glass bottles (Alaka et al., 2003).

The nutritional and bio-physical characteristics of Physalis (Husk tomato)

juice packaged in glass bottles and flexible laminated packs during storage under

refrigeration (5±1°C, 85-90%RH) for 6 months were studied by El-Sheikha et al.

(2009). Carotenoids, polyphenolic substances and ascorbic acid contents were

gradually reduced throughout cold storage, where this reduction was more

pronounced in juice packaged in flexible laminated packs. A slight increase in total

acidity was observed with cold storage prolongation, especially in juice packaged in

flexible laminated packs. Significant differences in color were found between the

same juice packaged either in glass bottles or in flexible laminated packs, where the

29

juice color was darker in flexible laminated packs. It was concluded that Physalis

(Husk tomato) juice packaged in glass bottles had higher storage stability than that

packaged in flexible laminated packs.

2.9 MICROBIOLOGY

2.9.1 Microbiology of sugarcane and other juices

Raw sugarcane juice was found to have 2.7x106 bacterial colonies per ml

and 4.8x105 yeast and mould count per ml of sample. E coli count was found to be

4.99x104 cfu/ml (Nagalakshmi, 1995).

Hassandar et al. (1992) conducted experiments on apple juice for microbial

load at various stages and after heat treatment at 70°C for one hour. Heat treatment

reduced the overall microbial load by 96.0 – 93.3% without any detrimental effect

on physico-chemical characteristics of the juice.

Similar results were obtained by Subbannayya et al. (2007) stating that

bacterial count in juice ranged from 105 to 107 cfu/ml. Salmonella, Shigella and

Vibrios were not isolated. Moreover presence of E.coli, other coliforms and

Enterococci indicated faecal contamination of juice.

According to Chauhan et al. (2002) the microbiological population (total

plate counts, and yeast and mold counts) increased during storage of sugarcane

juice. The extent of increase in microbial population was also higher at room

temperature as compared to refrigeration temperature. Highest counts were obtained

during storage of pasteurized juice followed by pasteurization with addition of

ascorbic acid followed by pasteurization with addition of citric acid. Addition of

potassium metabisulphite to juice further reduced the counts appreciably. Raw

sugarcane juice had 10 to 20 colonies of coliforms per 10 ml. The coliforms

disappeared after pasteurization and no coliform could be detected throughout the

storage.

30

Irradiation was less effective in reducing the yeast and mould population.

The lower dose of 0.7 and 1.4 kGy had a minimal effect: while 3.5 and 4.0 kGy

reduced the population by over 1 logs in fresh orange juice (Foley et al., 2002).

Fresh sugarcane juice sold by street vendors without any heat treatment in

São Carlos, São Paulo, Brazil were analysed for heterotrophic bacteria, total and

thermo-tolerant coliform counts, Salmonella, and parasites in the juice. 25% of

samples showed thermotolerant coliform levels were higher than allowed by

Brazilian standards. Salmonella spp. and parasites were absent in all samples.

Thermo-tolerant coliforms were detected on the hands of 37% of juice handlers, and

heterotrophic bacterial counts reached 2.0 x 103 cfu/per hand. Escherichia coli was

detected in one hand sample, and no Salmonella spp. was detected (Oliveira et al.,

2006).

A total of 52 fruit juice samples were analyzed by Tambekar et al. (2009) in

Amravati city, India, for presence of enteric bacterial pathogens. The dominant

bacterial pathogen present in juices were Escherichia coli (40%), followed by

Pseudomonas aeruginosa (25%), Salmonella spp. (16%), Proteus spp. (9%),

Staphylococcus aureus (6%), Klebsiella spp. (3%) and Enterobacter spp. (1%). The

highest bacterial contamination was observed in sweet lemon juice (35%),

pineapple (29%), pomegranate, apple and orange (12%) each.

Similar study was done in Nagpur city where fruit and vegetable juice

samples were analyzed for their microbiological quality. A total of 38 samples were

analysed for total viable count, total and fecal coliforms, staphylococci on mannitol

salt agar and salmonella. The total viable count in all the fruit and vegetable

samples were in the range of 2.0x104 – 4.6x106. Almost 50% of the fruit and

vegetable juices also showed the presence of Salmonella (Titarmare et al., 2009).

31

2.10 Organoleptic parameters

Preservation of Orange juice was done using potassium metabisulphite.

Preserved juice was stored at refrigerated temperature (1°C) without preservative

and at room temperature with preservative (potassium metabisulfite, 600 µg/kg) for

a period of 4 weeks. On sensory evaluation scores for flavour, acceptability and

taste of experimental juice and a control were comparable during first three weeks.

In 4th week the sweet and after taste was found to be considerably lower (Goyle

and Ojha, 1998).

Sugarcane juice beverage samples were prepared by pasteurizing the

sugarcane juice at 70°C for 10 minutes and adding citric acid (40mg/100ml),

ascorbic acid (40mg/100ml) and potassium metabisulphite (150ppm). The

sugarcane juice just after preparation was awarded sensory scores ranging between

7.5 to 8.5 for appearance, flavour and overall acceptability by the panelists. The

sensory scores reduced significantly (P<0.01) with the advancement of storage. A

significantly (P<0.01) lower reduction in sensory scores was observed in sugarcane

juice pasteurized after addition of citric acid and potassium metabisulphite followed

by pasteurization after addition of ascorbic acid and potassium metabisulphite,

pasteurization after addition of citric acid, pasteurization after addition of ascorbic

acid, and pasteurized only (Chauhan et al., 2002).

Unpasteurized and pasteurized sweet orange juices were filled in sterilized

and unsterilized bottles, stored at room temperature and refrigerated temperature.

Visual appearance of all the juice samples was maintained within highly acceptable

range during the entire period of storage but with the advancement of time,

deterioration in taste and flavor occurred which adversely affected the overall

acceptability of juice samples (Jain et al., 2003).

32

Chapter III

MATERIALS AND METHODS

The present study entitled “A Study on Increasing the Shelf Life of

Sugarcane Juice and Jaggery using Hurdle technology” was conducted at Post

Graduate and Research Centre, Acharya N.G.Ranga University, Hyderabad and

Quality control Lab, E.E.I, Rajendra Nagar, Hyderabad.

The details of the materials used and methods followed in carrying out the

work are described in this chapter.

3.1 PROCUREMENT OF RAW MATERIAL

Sugarcane juice was procured from local market, Hyderabad and jaggery

from Regional Agricultural Research Station (RARS), Ankapalle. All the chemicals

used in experimentation and analysis were of analytical grade, purchased from

standard Indian chemical companies. Glass (capacity 200ml), polyethylene

Terapthelate (PET) bottles (capacity 500ml), low density polyethylene pouches

(150 gauge) and paper bags for packing of juice and jaggery were obtained from

Begumpet, Hyderabad.

3.2. Experimental Details

The experiment has been divided into two parts:

3.2.1 Experiment – I

Experiment I consists of standardization of treatments.

3.2.1.1 Standardization of pasteurization temperature

Sugarcane juice gets fermented very fast. The major enzyme responsible for

this is invertase. Invertase causes inversion of sugars leading to spoilage of juice.

33

Plate – 2: Preserved sugar cane juice packed in glass bottles used in the present study

Plate – 1: Extraction of sugar cane

T1 T2 T3

34

Therefore the juice was heated at 70°C, 80°C and 90°C for 10 min. To

estimate the activity of enzyme reducing sugars content was analyzed using Lane

and Eyon Method (AOAC, 1965) (Appendix -B). It was found that invertase

enzyme was inactivated at 800C for 10 min.

3.2.1.2 Standardization of preservatives

Concentration of citric acid (0, 0.5, 1 and 1.5 gm/1000 ml), potassium

metabisulphite (KMS) (0, 50, 100, 150 and 200 ppm) were studied for optimization

of treatments on the basis of sensory evaluation of juice. Concentrations of citric

acid at 0.5 g/1000 ml and KMS at 150 ppm were found optimum to be for the

treatment of sugarcane juice.

3.2.2 Experiment –II

Experiment II consists of following treatments:

T1: Untreated sugarcane juice

T2: Pasteurization at 80°C for 10 min + chemical treatment (potassium

metabisulphite @ 150ppm and citric acid 0.05%)

T3: Pasteurization at 80°C for 10 min+ chemical treatment ( potassium

metabisulphite @ 150ppm and citric acid 0.05%)+ Sterilization at 80°C

for 20 min.

3.2.3. Experiment III

Experiment III consists of packaging details. Untreated (T1) and treated (T2

and T3) samples of sugarcane juice were packed in glass bottles, PET bottles and

LDPE pouches.

35

Plate – 3: Preserved sugar cane juice packed in PET bottles used in the present study

Plate – 4: Preserved sugar cane packed in LDPE pouches used in the present study

T1 T2 T3

T2 T1 T3

36

Plate – 5: Jaggery packed in LDPE used in the present study

Plate – 6: Jaggery packed in paper bag used in the present study

37

3.2.4. Experiment IV

Experiment IV consists of irradiation details. All the packed samples were

irradiated at three different doses i.e. 0.25 kGy, 0.5kGy and 1.0kGy.

3.2.5 Experiment V

Jaggery samples were packed in LDPE pouches and paper bags.

3.2.6 Experiment VI

All the packed samples were irradiated at three different doses i.e. 3 kGy, 5

kGy and 7 kGy.

J0: Control

J1: Irradiation treatment at 3 kGy

J2: Irradiation treatment at 5 kGy.

J3: Irradiation treatment at 7 kGy

3.3. RADIATION TREATMENT

Gamma Chamber 5000 was used for giving radiation treatments. It is

compact shelf shielded Cobalt 60 gamma irradiator providing an irradiation volume

of approximately 5000cc. The material for irradiation was placed in an irradiation

chamber located in vertical drawer inside the lead flask. This drawer can be moved

up and down with the help of a system of motorized drive, which enables precise

positioning of the irradiation chamber at the center of the irradiation field. Radiation

field was provided by a set of stationary Cobalt-60 source placed in a cylindrical

cage. The source was doubly encapsulated in corrosion resistant stainless steel

pencils and was tested in accordance with international standards. Two access holes

of 8 mm diameter are provided of service sleeves for gasses, thermocouple etc.

Mechanism for rotating/ stirring samples during irradiation is also incorporated.

38

Plate – 7: Irradiation Unit

Plate – 8: Irradiation of sugar cane juice

39

The lead shield provided around the source was adequate to keep the external

radiation field well within permissible limits.

The quantity absorbed dose (kGy) can be defined as the amount of energy

absorbed per unit mass of the matter at the point of interest.

1 Gy = 100 rads

1 kGy = 1000 Gy

3.3 SHELF LIFE

After all treatments and irradiation sugarcane juice was stored at room

(30±5°C) and low (4±2°C) temperature where as jaggery was stored at room

temperature (30±5°C) for a period of three months. Interval of analysis was one

month for both juice and jaggery.

No. of treatments

Sugarcane Juice : 3

Jaggery : 3

No. of replications : 3

Interval of analysis : 30 days

3.5 PARAMETERS STUDIED

3.5.1 Physico chemical: moisture, reducing sugars and total sugars.

3.5.2 Nutritional : vitamin-C, carbohydrates, and minerals (iron, calcium and

phosphorus)

3.5.3 Microbial : Viable Bacterial Count, Viable Yeast and Molds count

3.5.4 Organoleptic evaluation

40

3.5.1 Moisture

The moisture content of the samples was determined by using the method of

AOAC (1990) (Appendix-A).

3.5.2 REDUCING AND TOTAL SUGARS

Reducing and total sugars were determined by the method of Lane and

Eynon (AOAC, 1965) (Appendix -B).

3.5.3 ASCORBIC ACID

Ascorbic acid was determined by 2, 6-dichlorophenol indophenol visual

titration method (Ranganna, 1986) (Appendix -C).

3.5.4 CARBOHYDRATES

Carbohydrate content of the sample was analyzed by Anthrone method

given by Raghuramulu et al. (1983) (Appendix -D).

3.5.5 MINERALS

3.5.5.1. IRON

Iron was estimated by using α-- α --dipyridyl method of AOAC (1990)

(Appendix -F).

3.5.5.2 CALCIUM

Calcium was estimated using titrimetric method described by AOAC (1990)

(Appendix -G).

3.5.5.3. PHOSPHORUS

Phosphorus was estimated using the method of AOAC (2005) (Appendix -H).

41

3.6 MICROBIAL EXAMINATION

3.6.1 Viable Bacterial Count

For estimating microbial population in different samples, dilution plate

method was followed using plate count agar (Krishnakumar and Devadas, 2006a)

(Appendix - I).

3.6.2 Viable Yeast and Mold Count

Dilution plate method was followed for yeast and mold content using potato

dextrose agar (Krishnakumar and Devadas, 2006a) (Appendix -J).

3.7 ORGANOLEPTIC EVALUATION

The organoleptic scoring was done by a panel of 10 members in the sensory

evaluation laboratory of Post-Graduate and Research Centre using a score card

developed for the purpose. Score card was prepared keeping in view the quality

characteristics of the products. Descriptive terms were given to various quality

attributes like appearance, colour, flavor, taste and overall acceptability. Numerical

scores were assigned to each attribute (Periaym and Pilgrim, 1957).

A nine point hedonic scale (Appendix -K) was used to evaluate sugarcane

juice samples whereas five point hedonic scale (Appendix -L) was used to evaluate

jaggery samples. Score card was included in appendix.

3.8 STASTISTICAL ANALYSIS

The data was subjected to statistical analysis. Statistical analysis was done using

analysis of variance (ANOVA) (Snecdor and Coharn,1983).

42

Plate – 9: Microbial analysis of the preserved products

43

Plate – 10: Organoleptic Evaluation of the preserved products used in the present study

44

Chapter – IV

RESULTS AND DISCUSSION

The present investigation was conducted to study the change in the

shelf life of sugarcane juice and jaggery using hurdle technology. The data was

subjected to statistical analysis and the results obtained are presented in this chapter.

The results obtained have been divided into two sections:

4.1 Sugarcane juice

4.1.1. Composition of sugarcane juice

4.1.2. Shelf life of sugarcane juice

4.1.3. Nutritional profile of sugarcane juice

4.1.4. Microbial profile of sugarcane juice.

4.1.5. Sensory evaluation of sugarcane juice.

4.2 Jaggery

4.2.1. Composition of jaggery.

4.2.2. Shelf life of jaggery.

4.2.3. Nutritional profile of jaggery.

4.2.4. Microbial profile of jaggery

4.2.5. Sensory evaluation of jaggery.

4.1.1. Composition of sugarcane juice

Raw sugarcane juice was analyzed for physico - chemical, nutritional and

microbial parameters without any treatment. The results obtained are tabulated

below:

45

Table – 4.1. Composition of sugarcane juice

COMPOSITION AMOUNT ANALYZED Moisture 82.91% Ascorbic acid 3.39 mg/ 100ml Reducing sugars 0.50% Total sugars 16.32% Total carbohydrates 9.23 gm/100ml Viable bacterial count 4.56 X 106 cfu/ml Viable yeast and mold count 2.6 X 105cfu/ml

On lab analysis sugarcane juice was found to contain high moisture

percentage i.e. 82.91%, total sugars (16.328%), reducing sugars (0.50%),

3.39mg/100ml of ascorbic acid, 4.56 x106 viable bacterial count and 2.6x105 yeast

and mold count. Similar results were also reported by Krishnakumar and

Devadas,(2006b); Swaminathan (1991); Nagalakshmi, (1995) in cane juice for

moisture, total sugars, reducing sugars, ascorbic acid, viable bacterial and yeast &

mold count (Table 4.1).

4.1.2. Shelf life of sugarcane juice

4.1.2.1. Moisture content

The results presented in table - 4.2 and fig- 4.1, 4.2 showed significant

differences on shelf life of cane juice at 5% significant level. Among the

treatments, juice with treatment T3 (pasteurization at 80°C for 10 min + chemical

treatment + sterilization for 20 min at 80°C) was found to contain lowest moisture

percentage. This may be due to heat treatments which lead to reduction in moisture

content by evaporation during heating. Kumar, (2004) also reported similar results

for sapota pulp. PET bottles helped in maintaining the moisture content of the cane

juice. As PET bottles have good barrier water vapor and oxygen barrier properties

it showed less increase in moisture content. Irradiation doses at 1.0kGy also helped

in reducing the moisture content of the juice. During shelf life studies at room

(30±5°C) and low temperature (4±2°C), juice stored at low temperature (4±2°C)

46

showed minimum increase in the moisture content. Overall, shelf life of juice with

treatment T3 (pasteurization at 80°C for 10 min + chemical treatment + sterilization

for 20 min at 80°C), irradiation dose 1.0kGy packed in PET bottles was increased

upto 60 days at room temperature (30±5°C) and upto 90 days at low temperature

(4±2°C). Similar results were reported by Kaur et al. (1995) where pasteurization,

adding of preservatives and sterilization increased the shelf life of sugarcane juice

upto 24 weeks.

47

Table 4.2 Moisture content of sugarcane juice during storage

Treatments Irradiation doses

Packaging material

Shelf life at room temperature

Shelf life at low temperature

Zero day

30th day

60th day

Zero day

30th day

60th day

90th day

T2

I 0.25 GLASS 82.09 83.15 83.32 82.33 82.75 82.95 83.25

PET 80.40 82.68 83.56 80.40 81.86 82.09 83.64 LDPE 82.44 85.76 - 82.44 84.05 86.77 -

I 0.5 GLASS 81.92 82.81 83.00 82.29 82.60 82.78 82.68

PET 80.31 82.51 83.48 80.31 81.74 82.47 83.57 LDPE 82.38 85.43 - 82.38 83.54 86.53 -

I 1.0 GLASS 81.84 82.77 82.88 82.17 82.48 82.64 82.89

PET 80.23 82.34 83.35 80.23 81.66 82.34 83.43 LDPE 82.15 85.03 - 82.15 83.25 86.14 -

T3

I 0.25 GLASS 81.78 82.54 82.75 81.53 82.14 82.39 82.89

PET 79.82 82.05 83.13 79.82 81.41 82.26 83.43 LDPE 82.03 84.84 - 82.03 84.44 86.66 -

I 0.5 GLASS 81.81 82.30 82.52 81.44 82.06 82.27 82.34

PET 79.80 81.48 82.96 79.80 80.83 82.12 82.75 LDPE 81.84 84.94 - 81.84 83.16 85.03 -

I 1.0 GLASS 81.65 82.22 82.31 81.28 82.43 82.17 82.35

PET 79.65 81.37 82.72 79.65 80.74 82.05 83.04 LDPE 81.74 84.43 - 81.74 83.04 85.46 -

T*P*S T*P*S S.E m± 0.017347 0.059828

C.D (5%) 0.04891 0.16772 S S

*S:Significant level at 5%

48

Fig

4.1

Moi

stur

e co

nten

t of s

ugar

cane

juic

e st

ored

at r

oom

tem

pera

ture

49

Fig

4.2

Moi

stur

e co

nten

t of s

ugar

cane

juic

e st

ored

at l

ow te

mpe

ratu

re

50

4.1.3. Nutritional profile of sugarcane juice

4.1.3.1. Ascorbic acid content

The results presented in table- 4.3 and fig- 4.3, 4.4 recorded significant

differences (P > 0.05) in ascorbic acid content of sugarcane juice treated by

different methods. There was a significant decrease in ascorbic acid content during

treatments. Ascorbic acid content was significantly high in T1 (untreated juice) in

glass bottles (3.56%) and least in T3 (pasteurization at 80°C for 10 min + chemical

treatment+ sterilization for 20min at 80°C) in LDPE pouches (2.31%). As ascorbic

acid is heat sensitive pasteurization and sterilization had caused reduction in

ascorbic acid content in sugarcane juice. Decreased levels of ascorbic acid were

reported by Muhammad et al. (2010) on pasteurization of strawberry juice. As glass

bottles are chemically inert and absolute barriers to permeation to oxygen or water

vapor (Potter and Hotchkiss, 1996) glass bottles showed highest ascorbic acid

retention.

Also there was significant decrease (P>0.05) in ascorbic acid content with

increase in irradiation doses. 0.25kGy irradiation dose recorded maximum ascorbic

acid content in juice. According to Paul (1997) water soluble vitamins, thiamine,

pyridoxine and vitamin C are more susceptible to irradiation than riboflavin, niacin

or vitamin B12. There was significant decrease (P>0.05) in ascorbic acid content on

storage of juice at room (30±5°C) and low temperature (4±2°C). Loss of ascorbic

acid was found to be less at refrigerated temperature in comparison to room

temperature storage. According to Clara et al. (2007) concentration of ascorbic acid

decreased slowly in orange juice when stored at 2 or 10°C. Juice with treatment T2

(Pasteurization at 80°C for 10 min + Chemical treatments) at 0.25kGy dose in glass

bottles was found to have highest ascorbic acid content upto 90 days of storage.

51

Table 4.3 Ascorbic acid content of sugarcane juice during storage

Treatments Irradiation doses

Packaging material

Shelf life at room temperature

Shelf life at low temperature

Zero day

30th day

60th day

Zero day

30th day

60th day

90th day

T2

I 0.25 GLASS 3.17 2.70 2.26 3.17 2.83 2.32 2.36

PET 3.03 2.46 2.07 3.03 2.65 2.22 1.86 LDPE 2.81 2.54 - 2.81 2.74 2.53 -

I 0.5 GLASS 3.06 2.48 2.02 3.06 2.65 2.12 2.16

PET 2.86 2.27 1.86 2.86 2.42 2.21 1.74 LDPE 2.59 2.33 - 2.59 2.55 2.41 -

I 1.0 GLASS 2.96 2.10 1.85 2.96 2.45 2.10 1.97

PET 2.64 1.94 1.43 2.64 2.13 2.04 1.67 LDPE 2.31 2.03 - 2.31 2.17 2.07 -

T3

I 0.25 GLASS 2.74 1.94 1.54 2.74 2.14 1.89 1.86

PET 2.45 1.83 1.35 2.45 1.96 1.83 1.44 LDPE 2.15 1.87 - 2.15 2.13 1.95 -

I 0.5 GLASS 2.62 1.72 1.23 2.37 1.86 1.64 1.73

PET 2.37 1.40 1.06 2.37 1.86 1.64 1.23 LDPE 2.05 1.47 - 2.05 1.93 1.85 -

I 1.0 GLASS 2.44 1.51 0.95 2.44 1.86 1.73 1.62

PET 2.06 1.07 0.74 2.06 1.74 1.53 1.06 LDPE 1.97 1.14 - 1.97 1.88 1.73 -

T*P*S T*P*S S.E m± 0.01361 0.01804

C.D (5%) 0.03872 0.05059 S S

*S:Significant level at 5%

52

Fig

4.3

Asc

orbi

c ac

id c

onte

nt o

f sug

arca

ne ju

ice

stor

ed a

t roo

m te

mpe

ratu

re.

53

Fig

4.4

Asc

orbi

c ac

id c

onte

nt o

f sug

arca

ne ju

ice

stor

ed a

t low

tem

pera

ture

.

54

4.1.3.2. Reducing sugars

The results for reducing sugars were tabulated under table 4. 4 and fig 4.5, 4.6.

Treatments, packaging material and irradiation doses showed no significant

difference on reducing sugar content present in cane juice. But when juice was

stored at room (30±5°C) and low temperature (4±2°C) for three months there was a

significant increase in reducing sugar content of juice. The increase in reducing

sugars may be due to hydrolysis of sugars by acids or due to degradation of

disaccharides to monosaccharides. Increase in reducing sugars in sapota juice

(Reddy, 2004) and in watermelon ready to serve beverage (Farheen, 2004) were

also reported during storage.

The increase in reducing sugars was found to be less at low temperature

(4±2°C). The results obtained are in agreement with Chauhan et al. (2004) reported

lower increase in reducing sugars at low temperature in comparison to room

temperature.

Upto 60 days of storage, juice with treatment T2 (pasteurization at 80°C for 10

min + chemical treatment) with 0.5 kGy dose and treatment T3 (pasteurization at

80°C for 10 min + chemical treatment + sterilization for 20 min at 80°C) with 1.0

kGy recorded highest reducing sugar content (0.95%) at room temperature

(30±5°C). At low temperature (4±2°C) juice with treatment T3 (pasteurization at

80°C for 10 min + chemical treatment + sterilization for 20min at 80°C) with

1.0kGy dose recorded maximum reducing sugar content (0.88%) in PET bottles at

90 days of storage

55

Table 4.4 Reducing sugar content of sugarcane juice during storage

Treatments Irradiation doses

Packaging material

Shelf life at room temperature

Shelf life at low temperature

Zero day

30th day

60th day

Zero day

30th day

60th day

90th day

T2

I 0.25 GLASS 0.53 0.77 0.85 0.53 0.54 0.64 0.72

PET 0.52 0.86 0.87 0.52 0.66 0.76 0.82 LDPE 0.54 0.87 - 0.54 0.53 0.57 -

I 0.5 GLASS 0.53 0.70 0.77 0.53 0.55 0.61 0.69

PET 0.51 0.73 0.95 0.51 0.67 0.76 0.77 LDPE 0.53 0.82 - 0.53 0.55 0.63 -

I 1.0 GLASS 0.53 0.65 0.70 0.53 0.55 0.63 0.75

PET 0.53 0.84 0.94 0.53 0.71 0.80 0.83 LDPE 0.56 0.74 - 0.56 0.58 0.60 -

T3

I 0.25 GLASS 0.55 0.85 0.93 0.55 0.61 0.65 0.79

PET 0.54 0.74 0.87 0.54 0.66 0.82 0.80 LDPE 0.54 0.86 - 0.54 0.55 0.64 -

I 0.5 GLASS 0.56 0.86 0.94 0.56 0.62 0.68 0.76

PET 0.56 0.73 0.94 0.56 0.63 0.77 0.86 LDPE 0.55 0.74 - 0.55 0.56 0.66 -

I 1.0 GLASS 0.53 0.81 0.95 0.53 0.61 0.67 0.83

PET 0.55 0.66 0.95 0.55 0.69 0.82 0.88 LDPE 0.50 0.90 - 0.50 0.55 0.63 -

T*P*S T*P*S S.E m± 0.01625 0.01221

C.D (5%) 0.04582 0.03424 S S

*S:Significant level at 5%

56

Fig

4.5

Red

ucin

g su

gars

in c

ane

juic

e st

ored

at r

oom

tem

pera

ture

57

Fig

4.6

Red

ucin

g su

gars

in

cane

juic

e st

ored

at l

ow te

mpe

ratu

re

58

4.1.3.3. Total sugars

Treatments, packaging material and irradiation doses showed no significant

difference on total sugar content present in cane juice (Table- 4.5and fig 4.7,4.8).

Juice with treatment T1 (untreated juice) recorded highest total sugar content. A

significant reduction in total sugar content was noticed at all irradiation doses and

packaging materials. Irradiation dose at 0.25kGy and LDPE pouches was found to

maintain highest total sugar content in juice at zero day. Moreno et al. (2007) also

reported reduction in total sugar content on irradiation at medium doses (1.5kGy) in

mango fruit.

A significant decrease (P>0.05) in total sugar content of juice was observed

when it was stored at room and low temperature. The decrease in total sugars

content may be due breakdown of total sugars into reducing and other sugars. The

decrease in total sugar content was found to be less at low temperature (4±2°C) in

comparison to room temperature (30±5°C) storage. Similar results were reported

by Chauhan et al.(2002) for storage of sugarcane juice. Upto 30 days of storage at

room temperature (30±5°C), juice with treatment T2 (pasteurization at 800 C for 10

min + chemical treatment) irradiated at 0.25kGy stored in LDPE pouches recorded

highest total sugar content. After 30 days, the juice samples stored in LDPE

pouches were spoiled.

Hence juice with treatment T2 (pasteurization at 800 C for 10 min +

chemical treatment) at all irradiation doses (0.25, 0.5 and 1.0 kGy) in glass bottles

was found to be at par upto 90 days of storage period.

59

Table 4.5 Total sugar content of sugarcane juice during storage

Treatments Irradiation doses

Packaging material

Shelf life at room temperature

Shelf life at low temperature

Zero day

30th day

60th day

Zero day

30th day

60th day

90th day

T2

I 0.25 GLASS 15.77 15.45 15.22 15.77 15.65 15.64 15.62

PET 15.75 15.33 15.11 15.75 15.61 15.58 15.44 LDPE 16.75 16.21 - 16.75 16.66 16.53 -

I 0.5 GLASS 15.75 15.43 15.10 15.75 15.64 15.63 15.61

PET 15.74 15.32 15.08 15.74 15.59 15.57 15.42 LDPE 16.73 15.95 - 16.73 16.65 16.52 -

I 1.0 GLASS 15.75 15.42 14.99 15.75 15.64 15.62 15.60

PET 15.73 15.31 15.08 15.73 15.57 15.56 15.30 LDPE 16.73 15.94 - 16.73 16.65 16.41 -

T3

I 0.25 GLASS 15.49 15.40 14.85 15.49 15.48 15.47 15.46

PET 15.72 15.29 15.06 15.72 15.57 15.56 15.31 LDPE 16.73 15.90 - 16.73 16.63 16.42 -

I 0.5 GLASS 15.49 15.38 14.76 15.49 15.47 15.46 15.45

PET 15.71 15.26 15.03 15.71 15.45 15.43 15.11 LDPE 16.71 14.87 - 16.71 16.60 16.41 -

I 1.0 GLASS 15.48 15.26 14.56 15.48 15.46 15.45 15.32

PET 15.70 15.24 15.01 15.70 15.42 15.41 15.10 LDPE 16.71 14.84 - 16.71 16.59 16.23 -

T*P*S T*P*S S.E m± 0.00275 0.00243

C.D (5%) 0.00775 0.00683 S S

*S:Significant level at 5%

60

Fig

4.7

Tot

al su

gar

cont

ent o

f sug

arca

ne ju

ice

stor

ed a

t roo

m te

mpe

ratu

re

61

Fig

4.8

Tot

al su

gar

cont

ent o

f sug

arca

ne ju

ice

stor

ed a

t low

tem

pera

ture

62

4.1.3.4. Mineral estimation

There was no appreciable change in mineral content of sugarcane juice was

observed on storage. Untreated cane juice was analyzed for minerals (iron, calcium

and phosphorus) before and after storage. Before storage on lab analysis cane juice

was found to contain 2.20mg/100ml of iron, 16.23mg/100ml of calcium and 7.6mg/

100ml of phosphorus. Sankhla et al. (1999) also reported similar results for calcium

and iron in sugarcane juice. After 90 days of storage among all treatments juice

with treatment T3 (pasteurization at 800 C for 10 min + chemical treatment +

sterilization for 20 min at 800C) at irradiation dose of 1.0kGy was found to be best.

Therefore the best treatment was subjected to mineral estimation. At the end of the

storage period, juice with treatment T3 (pasteurization at 800 C for 10 min +

chemical treatment + sterilization for 20 min at 800C) contained 1.23mg/100ml of

iron, 14.07mg/100ml of calcium and 6.8mg/100ml of phosphorus (Table 4. 6).

Table 4. 6 Mineral estimation of sugarcane juice before and after storage

Minerals

estimation

Iron

(mg/100ml)

Calcium

(mg/100ml)

Phosphorus

(mg/100ml)

Before storage 2.20 16.23 7.6

After storage 1.23 14.07 6.8

4.1.4. Spoilage of juice

Untreated juice with or without irradiation stored at room and low

temperature was spoiled within 2-3 days. Also juice stored in LDPE pouches was

spoiled after 30 days at room temperature and after 60 days at low temperature.

Juice stored in glass and PET bottles was spoiled after 60 days at room temperature.

63

4.1.5. Microbial profile of sugarcane juice.

4.1.5.1. Viable Bacterial, yeast and mold count.

The results obtained for bacterial and yeast & mold count are presented in

table 4.7 and 4.8. The bacterial and yeast & mold estimation showed significant

differences (P>0.05) among all treatments in all packaging materials at different

irradiation doses. Highest microbial load was recorded in T1(untreated juice) packed

in LDPE pouches (4.88 X 106 cfu/ml) and least in T3 (pasteurization at 800 C for 10

min + chemical treatment+ sterilization for 20 min at 800C).

As heating destroys micro organism, T2 (pasteurization at 800 C for 10 min

+ chemical treatment) and T3 (pasteurization at 800C for 10 min + chemical

treatment + sterilization for 20min at 800C) treatments have shown reduced

microbial growth. More over addition of potassium metabisulphite and citric acid

had reduced the pH of juice further limiting the growth. Chauhan et al.(2002) also

reported similar findings on bacterial count in cane juice. PET and glass bottles

were found to be at par in preventing the growth of micro organisms as they have

good barrier properties. According to El-Sheikha et al. (2009) Physalis (Husk

tomato) juice packaged in glass bottles had higher storage stability than that

packaged in flexible laminated packs.

Irradiated samples recorded significantly lower bacterial count in comparison to

untreated samples (Reddy, 2004). The lower count of microorganism was due to

DNA damage of bacteria on exposure to radiation leading to cell death (Brennan,

2006). Least microbial growth was recorded at irradiation dose of 1.0 kGy.

Significant increase in microbial load was observed from zero day to 60 days of

storage at room (30±5ºC) and low (4±2 ºC) temperature in all packaging material

(fig 4.9 and 4.10). The increase was more in LDPE pouches. This may be due to

poor barrier properties of LDPE. Juice stored in LDPE pouches were spoiled after

30 days at room temperature and after 60 days at low temperature. Combination of

with treatment T3 (pasteurization at 800 C for 10 min + chemical treatment +

64

sterilization for 20 min at 800C) irradiated at 1.0kGy packed in glass bottles was

found to be best in terms of preventing the growth of microorganism in cane juice.

Krishnakumar and Devadas, (2006a) reported that increase in bacterial and yeast &

mold count in cane juice was less in glass bottles followed by polyethylene and

polypropylene after the storage of 60 days. According to Chumillas et al.(2007) no

bacterial growth was found in orange juice packed in glass and PET bottles.

65

Table 4.7. Viable bacterial count (value in 106) in sugarcane juice during storage

Treatments Irradiation doses

Packaging material

Shelf life at room temperature

Shelf life at low temperature

Zero day

30th day

60th day

Zero day

30th day

60th day

90th day

T2

I 0.25 GLASS 0.85 2.44 2.76 0.85 1.30 2.46 3.45

PET 1.95 2.83 3.89 1.95 2.53 3.25 4.24 LDPE 2.07 4.45 - 2.07 2.56 3.86 -

I 0.5 GLASS 0.73 2.31 2.63 0.73 1.26 2.20 3.07

PET 1.72 2.46 3.29 1.72 2.08 2.62 3.29 LDPE 1.86 4.20 - 1.86 2.31 3.13 -

I 1.0 GLASS 0.64 2.06 2.48 0.64 1.03 1.45 2.95

PET 1.39 2.16 2.86 1.39 1.06 1.44 3.05 LDPE 1.52 3.66 - 1.52 2.08 2.76 -

T3

I 0.25 GLASS 0.29 1.93 2.04 0.29 1.23 1.64 1.83

PET 0.86 1.87 2.43 0.86 1.23 1.81 2.83 LDPE 1.40 2.53 - 1.40 1.88 2.44 -

I 0.5 GLASS 0.18 1.84 1.93 0.18 1.06 1.45 1.64

PET 0.77 1.74 1.89 0.77 1.06 1.94 2.34 LDPE 1.24 2.25 - 1.24 1.63 2.25 -

I 1.0 GLASS 0.06 1.65 1.75 0.06 0.75 1.14 1.29

PET 0.32 1.57 1.59 0.32 0.66 1.36 2.13 LDPE 1.07 2.03 - 1.07 1.55 2.03 -

T*P*S T*P*S S.E m± 0.03797 0.02073

C.D (5%) 0.10707 0.05815 S S

*S:Significant level at 5%

66

Fig

4. 9

Via

ble

bact

eria

l cou

nt (v

alue

in 1

06 ) in

suga

rcan

e ju

ice

stor

ed a

t roo

m te

mpe

ratu

re

67

Fig

4.1

0 V

iabl

e ba

cter

ial c

ount

(val

ue in

106 ) i

n su

garc

ane

juic

e st

ored

at l

ow te

mpe

ratu

re

68

Table 4.8. Viable mold count (value in 105) in sugarcane juice during storage.

Treatments Irradiation doses

Packaging material

Shelf life at room temperature

Shelf life at low temperature

Zero day

30th day

60th day

Zero day

30th day

60th day

90th day

T2

I 0.25 GLASS 1.57 2.10 2.95 0.85 1.30 2.46 3.45

PET 0.93 1.27 2.21 1.95 2.53 3.25 4.24 LDPE 2.21 3.91 - 2.07 2.56 3.86 -

I 0.5 GLASS 1.31 1.87 2.71 0.73 1.26 2.20 3.07

PET 0.74 1.23 1.88 1.72 2.08 2.62 3.29 LDPE 1.99 3.63 - 1.86 2.31 3.13 -

I 1.0 GLASS 1.23 1.54 2.60 0.64 1.03 1.45 2.95

PET 0.64 0.95 1.75 1.39 1.06 1.44 3.05 LDPE 1.78 3.31 - 1.52 2.08 2.76 -

T3

I 0.25 GLASS 1.13 1.44 2.48 0.29 1.23 1.64 1.83

PET 0.44 0.91 1.52 0.86 1.23 1.81 2.83 LDPE 1.58 2.85 - 1.40 1.88 2.44 -

I 0.5 GLASS 0.92 1.28 2.33 0.18 1.06 1.45 1.64

PET 0.30 0.73 1.27 0.77 1.06 1.94 2.34 LDPE 1.37 2.36 - 1.24 1.63 2.25 -

I 1.0 GLASS 0.79 1.06 2.08 0.06 0.75 1.14 1.29

PET 0.21 0.36 1.07 0.32 0.66 1.36 2.13 LDPE 1.18 2.14 - 1.07 1.55 2.03 -

T*P*S T*P*S S.E m± 0.03242 0.02073

C.D (5%) 0.09142 0.05815 S S

*S:Significant level at 5%

69

Fig

4.1

1 V

iabl

e m

old

coun

t (v

alue

in 1

05 ) in

suga

rcan

e ju

ice

stor

ed a

t roo

m te

mpe

ratu

re.

70

Fig

4.1

2 V

iabl

e m

old

coun

t (v

alue

in 1

05 ) in

suga

rcan

e ju

ice

stor

ed a

t low

tem

pera

ture

.

71

4.1.5. Sensory evaluation of sugarcane juice.

4.1.5.1. Colour and appearance

Effect of treatments, packaging and irradiation was found to be non

significant (P>0.05) on colour of the juice during storage at room and low

temperature. On sensory evaluation T1 (untreated sugarcane juice) was found to be

darker in colour in comparison to treated samples. Heating has lead to the change in

colour of the juice (Table - 4.9 and fig 4.13, 4.14). Juice with treatment T3

(pasteurization at 800 C for 10 min + chemical treatment + sterilization for 20 min

at 800C) irradiated at 1.0 kGy stored in PET bottles was found to be best in terms of

colour till end of storage period. Kumar, (2004) also reported similar results in

sapota pulp.

72

Table 4.9 Color and appearance of sugarcane juice during storage

Treatments Irradiation doses

Packaging material

Shelf life at room temperature

Shelf life at low temperature

Zero day

30th day

60th day

Zero day

30th day

60th day

90th day

T2

I 0.25 GLASS 6.9 4.1 3.0 6.8 6.2 5.5 3.7

PET 6.6 5.5 4.2 7.0 6.3 5.8 3.7 LDPE 7.0 4.0 - 6.9 5.5 3.7 -

I 0.5 GLASS 6.9 4.1 3.1 7.4 7.4 5.2 3.0

PET 6.8 6.2 4.7 7.4 6.7 6.1 4.5 LDPE 7.3 4.8 - 7.3 5.6 3.9 -

I 1.0 GLASS 7.2 5.7 3.3 7.2 7.9 6.3 3.4

PET 7.3 6.8 5.0 7.5 6.9 6.6 5.2 LDPE 7.3 5.1 - 7.2 6.0 5. -

T3

I 0.25 GLASS 7.1 6.3 3.8 7.3 7.4 6.5 4.5

PET 7.4 7.2 5.2 7.6 7.4 7.1 5.8 LDPE 7.6 5.1 - 7.6 5.4 5.2 -

I 0.5 GLASS 8.1 6.8 4.6 8.3 8. 6.9 4.5

PET 8.0 7.5 5.5 8.1 7.6 7.4 6.0 LDPE 7.8 5.5 - 7.7 6.9 5.6 -

I 1.0 GLASS 8.6 6.7 4.8 8.6 8.4 7.0 5.4

PET 8.0 7.7 5.8 8.3 7.8 7.7 6.5 LDPE 7.8 5.7 - 8.1 7.3 5.9 -

T*P*S T*P*S S.E m± 0.22872 0.21271

C.D (5%) 0.63636 0.59224 NS NS

*NS: Non- Significant level at 5%

73

Fig

- 4.

13 C

hang

es in

col

or a

nd a

ppea

ranc

e o

f sug

arca

ne ju

ice

stor

ed a

t roo

m te

mpe

ratu

re.

74

Fig

- 4.

14 C

hang

es in

col

or a

nd a

ppea

ranc

e o

f sug

arca

ne ju

ice

stor

ed a

t low

tem

pera

ture

.

75

4.1.5.2. Flavor

Non significant differences (P>0.05) were observed between treatment,

irradiation and packaging material on flavor of cane juice. But on storage at room

and low temperature significant changes were observed in the scores for flavor of

cane juice (Table 4.10 and fig- 4.15,4.16). The decrease in scores was less at low

temperature. The decrease could be due to the loss of volatile aromatic substances

responsible for flavor during storage (Reddy, 2004). Treatment T3 (pasteurization at

800 C for 10 min + chemical treatment + sterilization for 20 min at 800C) with

irradiation dose of 1.0kGy in stored in PET bottles was found to be best in retention

of good scores for flavor during storage at room (30±5ºC) and low temperature

(4±2ºC).

76

Table 4.10 Flavor of sugarcane juice during storage

Treatments Irradiation doses

Packaging material

Shelf life at room temperature

Shelf life at low temperature

Zero day

30th day

60th day

Zero day

30th day

60th day

90th day

T2

I 0.25 GLASS 7.0 4.2 3.8 6.9 5.0 6.3 2.6

PET 7.1 6.4 3.7 7.3 7.2 6.7 4.5 LDPE 6.9 3.3 - 7.2 6.7 5.2 -

I 0.5 GLASS 7.2 3.7 3.3 7.3 5.9 6.2 3.7

PET 7.3 6.7 3.8 7.5 7.3 6.9 4.8 LDPE 7.2 4.0 - 7.6 7.3 5.6 -

I 1.0 GLASS 7.6 4.3 3.5 7.7 6.5 6.6 4.3

PET 7.6 7.4 4.0 7.7 7.5 7.1 5.0 LDPE 7.8 4.8 - 7.6 6.7 5.5 -

T3

I 0.25 GLASS 7.3 5.2 3.4 7.4 6.8 6.4 4.0

PET 7.7 7.4 4.4 7.9 7.6 7.3 5.2 LDPE 7.4 4.7 - 7.9 6.9 5.1 -

I 0.5 GLASS 7.1 5.2 3.8 7.0 6.8 6.5 4.3

PET 8.0 7.5 5.2 8.0 7.7 7.5 5.2 LDPE 7.7 5.5 - 8.0 7.0 5.5 -

I 1.0 GLASS 8.2 5.5 4.3 8.2 7.1 6.5 4.9

PET 8.0 7.8 5.7 8.2 7.8 7.8 5.7 LDPE 7.7 5.8 - 8.1 7.3 6.0 -

T*P*S T*P*S S.E m± 0.21836 0.20939

C.D (5%) 0.60755 0.58301 S S

*S: Significant level at 5%

77

Fig

- 4.1

5 C

hang

es in

flav

or o

f sug

arca

ne ju

ice

stor

ed a

t roo

m te

mpe

ratu

re.

78

Fig

- 4.

16 C

hang

es in

flav

or o

f sug

arca

ne ju

ice

stor

ed a

t low

tem

pera

ture

.

79

4.1.5.3. Taste

Effect of treatment, irradiation and packaging material on taste of cane juice

was found to be statistically non significant (P>0.05). Juice with treatment T3

(pasteurization at 800 C for 10 min + chemical treatment+ sterilization for 20min at

800C) and irradiation dose at 1.0 kGy showed highest scores for taste (Table 4.11

and fig-4.17, 4.18). Significant difference (P>0.05) were observed during storage at

room and low temperature. The decrease may be due to loss of volatile aromatic

substances responsible for taste as stated by Reddy, (2004). Also presence of

preservatives had lead to significant changes in taste. Scores obtained at low

temperature was found to be better in comparison to scores at room temperature.

Chauhan et al. (2002) also reported similar findings where sensory score decreased

on storage with decrease being less at low temperature than at room temperature. So

overall, juice with treatment T3 (pasteurization at 800 C for 10 min + chemical

treatment + sterilization for 20 min at 800C) irradiated at 1.0kGy dose packed in

PET bottles recorded highest scores for taste during storage period. (Table 4.37 and

fig-4.36).

80

Table 4.11 Taste of sugarcane juice during storage

Treatments Irradiation doses

Packaging material

Shelf life at room temperature

Shelf life at low temperature

Zero day

30th day

60th day

Zero day

30th day

60th day

90th day

T2

I 0.25 GLASS 7.2 4.3 3.1 6.9 5.0 6.3 2.6

PET 6.3 6.3 3.6 7.3 7.2 6.7 4.5 LDPE 6.6 2.6 - 7.2 6.7 5.2 -

I 0.5 GLASS 4.8 4.8 3.3 7.3 5.9 6.2 3.7

PET 6.7 6.4 3.8 7.5 7.3 6.9 4.8 LDPE 7.0 3.6 - 7.6 7.3 5.6 -

I 1.0 GLASS 7.6 4.6 4.4 7.7 6.5 6.6 4.3

PET 7.0 6.8 4.2 7.7 7.5 7.1 5.0 LDPE 7.3 3.9 - 7.6 6.7 5.5 -

T3

I 0.25 GLASS 7.6 4.8 3.3 7.4 6.8 6.4 4.0

PET 7.5 7.0 4.8 7.9 7.6 7.3 5.2 LDPE 7.5 4.6 - 7.9 6.9 5.1 -

I 0.5 GLASS 7.5 5.6 4.3 7.0 6.8 6.5 4.3

PET 7.9 7.4 5.0 8.0 7.7 7.5 5.2 LDPE 8.0 5.2 - 8.0 7.0 5.5 -

I 1.0 GLASS 8.2 5.9 4.2 8.2 7.1 6.5 4.9

PET 8.0 7.6 5.5 8.2 7.8 7.8 5.7 LDPE 8.1 5.5 - 8.1 7.3 6.0 -

T*P*S T*P*S S.E m± 0.23432 0.20939

C.D (5%) 0.65194 0.58301 S S

*S: Significant level at 5%

81

Fig

- 4.

17 C

hang

es in

tast

e of

suga

rcan

e ju

ice

stor

ed a

t roo

m te

mpe

ratu

re.

82

Fig

- 4.

18 C

hang

es in

tast

e of

suga

rcan

e ju

ice

stor

ed a

t low

tem

pera

ture

.

83

4.1.5.4. Overall acceptability

The interaction between treatments, packaging and irradiation doses during

storage at room and low temperature was found to be non- significant at 5%

significant level (table 4.12 and fig 4.19,4.20). Juice with treatment T3

(pasteurization at 800 C for 10 min + chemical treatment + sterilization for 20 min

at 800C) recorded highest scores for overall acceptability. Among the three

packaging material PET was found to be best in maintaining the scores. Irradiation

did not affect the scores for overall acceptability. Scores at irradiation dose 1.0kGy

was found to be better in comparison to other two doses (i.e. 0.25 and 5kGy).

Overall juice with treatment T3 (pasteurization at 800 C for 10 min + chemical

treatment + sterilization for 20 min at 800C) with irradiation dose at 1.0kGy packed

in PET bottles was found be best in terms of overall acceptability. Chauhan et

al.(2002) also reported the same findings in cane juice stored at low temperature.

84

Table 4.12 Overall acceptability of sugarcane juice during storage

Treatments Irradiation doses

Packaging material

Shelf life at room temperature

Shelf life at low temperature

Zero day

30th day

60th day

Zero day

30th day

60th day

90th day

T2

I 0.25 GLASS 7.2 4.4 3.3 7.3 5.3 5.4 3.5

PET 6.7 5.8 3.1 7.1 6.8 6.2 3.8 LDPE 7.0 3.8 - 7.2 5.0 4.7 -

I 0.5 GLASS 6.8 4.8 3.4 6.8 5.5 6.5 3.5

PET 6.9 6.7 3.5 7.0 7.1 6.5 4.0 LDPE 7.1 4.0 - 6.8 5.0 5.1 -

I 1.0 GLASS 7.5 5.5 3.3 7.6 5.7 6.4 4.0

PET 7.3 7.1 3.5 7.4 7.1 6.8 4.1 LDPE 7.4 4.1 - 7.4 6.3 5.3 -

T3

I 0.25 GLASS 7.3 5.1 3.2 7.4 6.4 6.3 4.0

PET 7.2 7.1 4.1 7.5 7.1 7.0 5.0 LDPE 7.4 4.7 - 7.2 6.2 5.7 -

I 0.5 GLASS 7.9 5.3 3.7 7.9 6.6 6.5 4.1

PET 7.9 7.3 4.7 7.8 7.4 7.3 5.1 LDPE 7.9 5.0 - 7.5 5.8 5.8 -

I 1.0

GLASS 7.8 5.4 3.8 8.1 7.6 6.7 4.3 PET 7.9 7.7 5.0 8.2 7.9 7.6 5.3

LDPE 7.9 5.9 - 7.6 7.3 6.2 -

T*P*S T*P*S S.E m± 0.20593 0.19610

C.D (5%) 0.57294 0.54600 NS NS

*NS: Non - Significant level at 5%

85

Fig

- 4.

19 C

hang

es in

ove

rall

acce

ptab

ility

of s

ugar

cane

juic

e st

ored

at r

oom

tem

pera

ture

.

86

Fig

- 4.2

0. C

hang

es in

ove

rall

acce

ptab

ility

of s

ugar

cane

juic

e st

ored

at l

ow te

mpe

ratu

re.

87

4.2.1. Composition of jaggery

Fresh jaggery was analyzed for physico - chemical, nutritional and microbial

parameters.

Table -4.13. Composition of jaggery

COMPOSITION AMOUNT ANALYZED

Moisture 2.8245 % Sucrose 70.8631% Reducing sugars 9.2356% Total carbohydrates 96.34% Viable bacterial count 2.45X 106 cfu/gm Viable yeast and mold count 3.16 X 103 cfu/gm

Jaggery was analyzed before storage for physico - chemical, nutritional and

microbial parameters. On estimation jaggery was found to contain 2.82 % moisture

content, 70.86% sucrose content, 9.23 % reducing sugars, 2.45X106 cfu/gm

bacterial population and 3.16X 103 yeast and mold count. Similar values for

moisture, sucrose, reducing sugars, bacterial and yeast & mold count was reported

by Rao et al. (2007); Singh et al. (2009). Mandal et al. (2007b) reported 9250 /g of

fungal load in fresh jaggery (Table 4.13).

4.2.2. Shelf life of jaggery

4.2.2.1. Moisture content

The results presented in table -4.14 and fig-4.21 showed significant changes

(P>0.05) in moisture content at all irradiation doses in both the packaging material

(LDPE and paper bags). Irradiated samples showed significant increase in moisture

content in comparison to non - irradiated samples. The increase may be due to

release of moisture from inner molecules of jaggery. Jaggery irradiated at 7.0 kGy

showed highest moisture content. Among the two packaging material paper bags

showed highest moisture content and LDPE was found to be best in preventing the

ingress of moisture because of good water vapor and oxygen barrier properties.

88

Similar findings were reported by Mandal et al. (2006), according to him

LDPE was found to be the best packaging material in preventing the ingress of

moisture. Therefore jaggery stored in LDPE pouches irradiated at 3.0kGy showed

least moisture content among the irradiated samples upto 90 days of storage at room

temperature (30±5ºC).

Table -4.14. Moisture content of jaggery during storage

TREATMENTS PACKAGING MATERIAL

STORAGE DAYS ZERO DAY

30th DAY

60th DAY

90th DAY

J0 LDPE 2.80 2.97 3.11 3.17

PAPER 2.90 3.20 3.75 4.11

J1 LDPE 3.69 3.70 3.74 3.83

PAPER 3.27 3.57 3.87 4.07

J2 LDPE 3.69 3.70 3.74 3.83

PAPER 3.62 4.04 4.56 5.33

J3 LDPE 3.86 3.97 4.09 4.26

PAPER 3.89 4.31 5.10 6.39 J*P*S

S.Em± 0.04944 C.D.(5%) 0.13970

S *S:Significant level at 5%

4.2.3. Nutritional profile of jaggery

4.2.3.1. Reducing sugars

The interaction between irradiation and packaging material was found to be

statistically non significant (P>0.05) on reducing sugars present in jaggery (Table

4.15). Jaggery with irradiation dose of 7.0kGy showed highest reducing sugar

content. Though increase in reducing sugar was observed during storage period

(fig- 4.22). The significant increase in reducing sugars may be due to hydrolysis of

sugars by acids and also may be due to degradation of disaccharides to

monosaccharides. Increase in reducing sugar was less in LDPE pouches during the

storage period because it had better water vapor barrier properties. Mandal et al.

(2007b) also reported increase of reducing sugars during storage. He also reported

that LDPE was found to be best in preventing the increase of sugars.

89

Fig – 4.21 Moisture content of jaggery during storage

Fig – 4.22 Reducing sugars of jaggery during storage

90

Table -4.15. Reducing sugars of jaggery during storage

TREATMENTS PACKAGING MATERIAL

STORAGE DAYS ZERO DAY

30th DAY

60th DAY

90th DAY

J0 LDPE 9.33 9.46 9.64 9.73

PAPER 9.41 9.86 10.26 10.66

J1 LDPE 10.09 10.35 10.60 10.79

PAPER 10.11 10.68 10.90 11.30

J2 LDPE 12.29 12.56 12.88 12.96

PAPER 12.31 12.75 13.10 13.52

J3 LDPE 12.87 13.08 13.21 13.51

PAPER 12.87 13.10 13.56 13.90 J*P*S

S.Em± 0.03855 C.D.(5%) 0.10894

S *S:Significant level at 5%

4.2.3.2. Sucrose content

Non significant differences (P>0.05) were noticed between irradiation doses

and packaging materials on sucrose content (Table 4.16 and fig-4.25). Jaggery with

irradiation dose 3.0 kGy showed highest sucrose content in all the samples. During

storage period sucrose percentage decreased significantly in irradiated samples.

Irradiated samples recorded highest sucrose percentage on zero day and lowest at

the end of storage period (90 days). The decrease in sucrose is due to inversion of

non reducing sugars (sucrose) to reducing sugars. The fall of sucrose was more

prominent in paper bags. LDPE pouches prevented the fall of sucrose to a great

extent. Similar results were reported by Mandal et al. (2006). Overall jaggery

sample irradiated at 3.0 kGy stored in LDPE pouches maintained sucrose content

till the end of the storage period (90 days).

91

Table -4.16. Sucrose content of jaggery during storage.

TREATMENTS PACKAGING MATERIAL

STORAGE DAYS ZERO DAY

30th DAY

60th DAY

90th DAY

J0 LDPE 70.95 69.91 69.48 69.23 PAPER 70.94 67.79 65.49 63.81

J1 LDPE 64.56 64.32 64.10 63.84 PAPER 63.17 62.89 60.76 59.49

J2 LDPE 59.39 59.14 58.89 58.71 PAPER 59.33 58.35 57.63 56.75

J3 LDPE 54.37 54.27 54.16 53.91 PAPER 54.43 53.86 52.54 51.16

J*P*S S.Em± 0.00799 C.D.(5%) 0.22589 S

*S:Significant level at 5%

4.2.3.3. Mineral estimation

There was no appreciable change in mineral content of jaggery was found during

storage. Jaggery was analyzed for minerals before storage. Jaggery being a rich

source of minerals, was found to contain iron 5.88mg/100gm, calcium

11.23mg/100gm and 4.8mg/100gm of phosphorus. Similar results were reported by

Asokan, (2009) for minerals present in jaggery. After storage, jaggery stored in

LDPE pouches irradiated at 7kGy dose was found to be best upto 90 days and was

found to contain 4.325mg of iron, 10.98 mg of calcium and 4.34mg of phosphorus

in 100gm of jaggery (Table 4.17).

Table 4.17. Mineral estimation of jaggery before and after storage

Minerals

estimation

Iron

(mg/100gm)

Calcium

(mg/100gm)

Phosphorus

(mg/100gm)

Before storage 5.88 11.23 4.8

After storage 4.32 10.98 4.3

92

Fig – 4.23 Sucrose content during storage

93

4.2.4. Microbial profile of jaggery.

4.2.4.1. Viable Bacterial, yeast and mold count.

Effect of irradiation and packaging materials was found to be statistically

non significant (P>0.05) on viable bacterial, yeast & mold counts in jaggery (Table-

4.18 and fig 4.26). On zero day non - irradiated samples were found to have highest

microbial population where as all irradiated samples showed no microbial growth.

The lower count of bacteria, yeast and mold was due to DNA damage of bacteria on

exposure to radiations leading to cell death (Brennan,2006). With the increase in

storage period microbial population increased significantly upto 90 days. The

increase in bacterial count was due to increase in moisture of jaggery. Singh et al.

(2009) observed higher microbial growth in stored jaggery. Samples irradiated with

7.0kGy dose showed least microbial growth. Among the two packaging material

samples stored LDPE was found to be best in increasing the shelf life of jaggery

upto 90 days.

Table -4.18. Viable bacterial count in jaggery during storage

(value in 106)

TREATMENTS PACKAGING MATERIAL

STORAGE DAYS ZERO DAY

30th DAY

60th DAY

90th DAY

J0 LDPE 2.23 2.76 3.43 4.00 PAPER 2.80 3.46 4.50 6.16

J1 LDPE 0.00 0.66 0.88 1.14 PAPER 0.00 1.73 2.40 4.90

J2 LDPE 0.00 0.68 0.75 0.97 PAPER 0.00 0.80 1.63 4.33

J3 LDPE 0.00 0.48 0.57 0.78 PAPER 0.00 0.44 1.73 3.36

J*P*S S.Em± 0.16666

C.D.(5%) 0.47095 S

*S:Significant level at 5%

94

Fig – 4.24. Viable bacterial count in jaggery during storage

(Value in 106)

Fig – 4.25 Viable yeast and mold count in jaggery during storage

95

Table -4.19. Viable yeast and mold count in jaggery during storage (value in 103)

TREATMENTS PACKAGING MATERIAL

STORAGE DAYS ZERO DAY

30th DAY

60th DAY

90th DAY

J0 LDPE 3.16 3.60 4.13 5.16

PAPER 3.23 4.66 5.83 7.10

J1 LDPE 0.00 0.63 0.80 1.04

PAPER 0.00 2.56 3.06 4.46

J2 LDPE 0.00 0.58 0.64 0.91

PAPER 0.00 1.83 3.63 4.60

J3 LDPE 0.00 0.32 0.46 0.62

PAPER 0.00 1.19 2.46 4.23 J*P*S

S.Em± 0.15457 C.D.(5%) 0.43670

S *S:Significant level at 5% 4.2.5. Sensory evaluation of jaggery.

4.2.5.1. Colour

Non significant interaction (P>0.05) was found between irradiation and

packaging material on colour of jaggery during storage (Table 4.20 and fig-4.28).

Non – irradiated samples recorded highest scores for color in compare to irradiated

samples.

Table - 4.20. Colour of jaggery during storage. Treatments PACKAGING

MATERIAL STORAGE DAYS

ZERO DAY

30th DAY

60th DAY

90th DAY

J0 LDPE 4.6 4.3 4.1 3.9 PAPER 4.6 4.3 4.1 3.9

J1 LDPE 4.4 3.9 3.8 3.6 PAPER 4.1 3.9 3.8 3.6

J2 LDPE 4.4 3.8 3.7 3.6 PAPER 4.4 4.0 3.7 3.6

J3 LDPE 4.0 3.70 3.5 3.4 PAPER 4.1 3.7 3.5 3.4

J*P*S S.Em± 0.20241

C.D.(5%) 0.56343 NS

*NS: Non- Significant level at 5%

96

Fig – 4.26 Changes in Colour of jaggery during storage.

Fig – 4.27 Changes in texture of jaggery during storage.

97

4.2.4.2. Texture

Non significant interaction (P>0.05) was found between irradiation and

packaging material on texture of jaggery during storage (Table 4.21 and fig-4.29).

Table -4.21. Texture of jaggery during storage.

TREATMENTS PACKAGING MATERIAL

STORAGE DAYS ZERO DAY

30th DAY

60th DAY

90th DAY

J0 LDPE 4.3 4.1 3.9 3.6 PAPER 4.4 4.1 3.9 3.6

J1 LDPE 3.7 3.6 3.4 3.5 PAPER 3.7 3.6 3.4 3.5

J2 LDPE 3.6 3.5 3.3 3.2 PAPER 3.6 3.1 3.3 3.2

J3 LDPE 3.3 3.2 3.0 2.9 PAPER 3.2 3.2 3.0 2.9

J*P*S S.Em± 0.17280

C.D.(5%) 0.48101 NS

*NS: Non-Significant level at 5%

4.2.4.3. Taste

The interaction between irradiation and packaging material was found to be

non significant (P>0.05) during storage period on taste of jaggery (Table 4.22 and

fig- 4.30).

4.2.4.5. Overall Acceptability

The interaction between irradiation and packaging material in jaggery was

found to be non significant (P>0.05) during storage period on overall acceptability

(Table 4.23 and fig 4.32).

98

Table -4.22. Taste of jaggery during storage.

TREATMENTS PACKAGING MATERIAL

STORAGE DAYS ZERO DAY

30th DAY

60th DAY

90th DAY

J0 LDPE 4.5 4.3 4.2 3.8 PAPER 4.5 4.3 4.2 3.8

J1 LDPE 4.5 4.2 4.2 3.9 PAPER 4.5 4.2 4.2 3.9

J2 LDPE 4.4 4.2 4.0 3.7 PAPER 4.4 4.1 4.0 3.7

J3 LDPE 4.4 4.4 3.8 3.6 PAPER 4.4 4.4 3.8 3.6

J*P*S S.Em± 0.20506

C.D.(5%) 0.57079 NS

*NS: Non-Significant level at 5%

Table - 4.23. Overall acceptability of jaggery during storage.

TREATMENTS PACAKGING MATERIAL

STORAGE DAYS ZERO DAY

30th DAY

60th DAY

90th DAY

J0 LDPE 4.5 4.1 4.0 3.8

PAPER 4.4 4.1 4.0 3.8

J1 LDPE 3.7 3.5 3.4 3.3

PAPER 3.6 3.5 3.4 3.3

J2 LDPE 3.4 3.3 3.1 2.8

PAPER 3.4 3.3 3.1 2.8

J3 LDPE 3.6 3.2 3.0 2.6

PAPER 3.3 3.2 3.0 2.6 J*P*S

S.Em± 0.16126 C.D.(5%) 0.44889

NS *NS: Non-Significant level at 5%

99

Fig – 4.28 Changes in taste of jaggery during storage.

Fig – 4.29 Changes in overall acceptability of jaggery during storage

100

Sugarcane juice is highly fermentable and contains about 15-18% sucrose,

0.5% reducing sugars and adequate amount of organic nitrogen and mineral salts for

microbial growth. Its pH ranges from 5.0-5.5 making it selective for growth of

acidophilic microorganism especially yeast and lactic acid bacteria. Large

population of yeast favors the ethanol production at the expense of sucrose. The

microbial contamination of the juice is usually extremely high, typical viable counts

being 108-109 cells/ml of juice. The major loss of sugar occurs due to inversion of

sucrose in raw sugar cane juice and other types of degradation of the juice caused

by bacterial activities, enzymes and other biological factors (Solomon, 2009).

Invertases (β-D-fructofuranosidase, E.C. 3.2.1.26) are the key enzymes

involved in sucrose metabolism in sugarcane plants. These enzymes are responsible

for inversion in cane and milled juice (Sachdeva et al., 2003).

Sugarcane juice is also spoiled by bacteria such as, Leuconostoc,

Enterobacter, Flavobacteruim, Micrococcus, Lactobacillus, Actinomyces. Among

yeast and molds, Aspergillus, Cladosporium, Monilla, Penicillium, Saccharomyces,

Candidia, Pichia, Torulopsis are responsible for spoilage (Frazier and Westhoff,

2007).

Jaggery is mostly spoiled during the monsoon period because of invert

sugars and mineral salts. Moisture is the main culprit in the deterioration of jaggery

quality. Due to continuous inversion of sucrose by microbes, more invert sugars are

formed which absorbs more moisture and this way a noxious circle is formed. The

process continues till gur (jaggery) becomes soft and loose. At this time, several

fungi develop, particularly molds (Aspergilla and Peniciliia) and members of the

family Mucroceae which reduces the shelf life of jaggery (Ghosh et al., 1998).

All the above factors mentioned are responsible for decreasing the quality

and shelf life of cane juice and jaggery.

101

Therefore combinations of hurdles were tried in the present work in an

attempt to improve the shelf life of cane juice and jaggery. Following combinations

were used for treating sugarcane juice; pasteurization, chemical preservatives (KMS

and Citric acid), sterilization, irradiation and packaging. As invertase is the main

culprit in causing fermentation of juice, the juice was heated to a temperature of

800C for 10 min which was found sufficient to inactivate the invertase enzyme.

Pasteurization further helped in controlling fermentation and spoilage of juice.

Furthermore cane juice is susceptible to microorganism so chemical preservatives,

sterilization and irradiation helped in maintaining the quality of juice by reducing

microbial load from juice. Because of good barrier properties, the packaging

material further contributed in increasing the shelf life of juice by preventing

moisture and oxygen ingress into the juice.

Jaggery was irradiated at different doses and packed in LDPE and paper

bags. As hygroscopic nature of jaggery decreases its shelf life, LDPE was found to

be best in preventing moisture uptake in jaggery. As jaggery is also susceptible to

fungal growth due to high moisture content, irradiation reduced the microbial load

therefore preventing the inversion of sugars in jaggery, which is mainly responsible

for deteriorating the quality of jaggery. Hence the combination of packaging and

irradiation was found to increase the shelf life of jaggery significantly.

The ultimate aim of using any hurdle technology for food preservation is to

improve shelf life with minimum impact on the nutritional and sensory qualities. It

can therefore be recommended that in preservation of any food material, a

combination of hurdles, based on the physico-chemical and microbial susceptibility

of the food product need to be identified and employed.

102

Chapter V

SUMMARY AND CONCLUSION

The present research programme was undertaken to increase the shelf life of

sugarcane juice and jaggery using hurdle technology. Investigations were carried

out at the laboratory of Post Graduate and Research Centre, Acharya N.G.Ranga

University, Hyderabad and Quality control Lab, E.E.I, Rajendra Nagar, Hyderabad.

Sugarcane juice is commonly used as delicious drink during summers all

over India. Being a nutritious product containing natural sugars, minerals and

organic acids, sugarcane juice has many medicinal properties but the major problem

faced with sugarcane juice is that it gets spoiled quickly due to action of enzymes

and microorganism.

Jaggery being another product obtained from sugarcane, is highly nutritious

and has many health benefits. Due to its highly hygroscopic nature, the keeping

quality of jaggery is reduced.

Therefore an attempt was made to develop a protocol for improving shelf

life of sugarcane juice and jaggery using heat, chemicals and irradiation as hurdles

for maintaining the quality. The results drawn from the present study are

summarized as follows.

Sugarcane juice was collected from local market, Hyderabad.

Invertase is the major enzyme responsible for spoilage of cane juice.

Therefore pasteurization temperature and time was standardized. It was

found that heating of juice to a temperature of 800C for 10 min was

sufficient to deactivate the enzyme.

103

Preservatives potassium metabisulphite (150 ppm) and citric acid (0.05%)

was used. Their concentrations were also standardized on the basis of

sensory evaluation.

The following treatments were standardized for treating sugarcane juice:

T1 : Untreated sugarcane juice

T2: Pasteurization at 800C for 10 min + chemical treatment

(potassium metabisulphite @ 150ppm and citric acid 0.05%)

T3: Pasteurization at 80 0C for 10 min + chemical treatment

(potassium metabisulphite @ 150ppm and citric acid

0.05%)+ Sterilization at 800 C for 20 min.

After these treatments sugarcane juice was packed in glass bottles, PET

bottles and LDPE pouches. After packaging sugarcane juice was subjected

to irradiation. Cane juice was irradiated at 0.25 kGy, 0.5kGy and 1.0kGy.

Non irradiated and irradiated samples were kept for storage upto 90 days at

room (30±50C) and refrigerated temperature (4±20C). Samples were

analyzed for physico - chemical, microbial and sensory parameters at an

interval of 30 days till it remained in acceptable condition.

Before storage, raw sugarcane juice was analyzed for its physico - chemical

nutritional and microbial parameters. On analysis it was found that

sugarcane juice contains 82.91% moisture content, 3.39 mg/100ml of

ascorbic acid, 0.50% of reducing sugars and 16.328% of total sugars,

9.23gm/100ml total carbohydrates.

104

Sugarcane juice was found to be good source of minerals. Fresh cane juice

contained 16.23mg/100ml of calcium, 2.20mg/100ml iron and 7.6mg/100ml

of phosphorus.

Fresh cane juice is susceptible to micro-organisms. Sugarcane juice was

found to contain 4.56X106 cfu/ml of bacterial population and 2.6X 105 of

yeast and mold population.

Untreated juice with or without irradiation stored at room and low

temperature was spoiled in few days. Also juice stored in LDPE pouches

was spoiled after 30 days at room temperature and after 60 days at low

temperature. Juice stored in glass and PET bottles was spoiled after 60 days

at room temperature.

Among all the treatments, juice with treatment T3 (pasteurization at 800 C

for 10 min + chemical treatment + sterilization for 20 min at 800C) was

found to be best treatment.

Irradiation dose at 1.0kGy was found to be best in maintaining the shelf life

of juice during the storage period.

Among the three packaging material juice packed in glass and PET bottles

was found to be at par. LDPE proved to be least effective in maintaining the

quality of the juice.

Overall treatment T3 (pasteurization at 800 C for 10 min + chemical

treatment + sterilization for 20 min at 800C) with irradiation dose at 1.0kGy

packed glass and PET stored at low temperature (4±2ºC) was found to be

best combination in increasing the shelf life of cane juice upto 90 days.

105

There was significant decrease (P>0.05) in ascorbic acid content because of

heating and irradiation. The decrease was less in glass bottles and highest in

LDPE pouches due to its poor oxygen and water vapor barrier properties.

Significant decrease of ascorbic acid was found during storage at both room

and low temperature.

Treatment T2 (Pasteurization at 800C for 10 min + Chemical treatments) at

0.25kGy dose in glass bottles was found to be best in retaining the ascorbic

acid till the end of the storage period.

Non significant differences (P>0.05) were found between treatments,

packaging materials on reducing sugars and total sugars. Irradiation didn’t

showed any significant changes on reducing sugars but a decrease in total

sugars was observed at all irradiation doses in juice. Also significant

increase (P>0.05) in reducing sugars content and decrease in total sugar was

observed during storage at room and low temperature.

Significant differences (P>0.05) were found among all treatments in all

packaging materials on microbial count of juice. Heat treatment and

chemical treatment was found to reduce bacterial and yeast and mold growth

in cane juice samples.

PET and glass bottles were found to be at par in preventing the growth of

micro organisms as they have good barrier properties. Irradiation has

decreased the microbial load upto great extent and 1.0kGy was found to be

best in reducing microbial load. Viable bacterial, yeast and mold count was

increased during storage at room and low temperature but the increase was

less at low temperature.

106

Treatments, packaging materials and irradiation were found to have no

effect on organoleptic properties of juice except for the colour. There was

change in colour on heating. Significant differences (P>0.05) were

observed during storage at room and low temperature on sensory properties

of juice.

After storage treatment T3 (pasteurization at 800 C for 10 min + chemical

treatment + sterilization for 20 min at 800C) with irradiation dose 1.0kGy

was found to be best till the end of storage period. At the end of the storage

period treatment T3 (pasteurization at 800 C for 10 min + chemical treatment

+ sterilization for 20 min at 800C) contained 9.47gm of carbohydrates,

14.07mg/100ml of calcium, 1.232mg/100ml of iron and 6.8mg/100ml of

phosphorus.

Jaggery was procured from RARS, Ankapalle. Fresh jaggery was analyzed

for physico – chemical, nutritional and microbial parameters. Jaggery was

found to contain 2.82% moisture content, 70.86% sucrose, 9.23% reducing

sugars 96.34% and carbohydrates. It also contained 11.23mg of calcium,

5.88mg of iron and 4.8mg of phosphorus in 100 gm of jaggery. Jaggery

contained 2.45X106 cfu/gm viable bacterial count and 3.1676 X103 cfu/gm

yeast and mold.

Jaggery was packed in LDPE pouches and paper bags. After packaging it

was subjected to irradiation at 3, 5 and 7 kGy doses. Irradiated and non

irradiated samples were stored at room temperature upto 90 days.

Irradiation dose of 7.0kGy was found to be best in maintaining the keeping

quality of jaggery. Furthermore, LDPE as a packaging material helped in

increasing the shelf life of jaggery upto 90 days.

107

Moisture content was found to increase on irradiation. Highest moisture

content was observed at 7.0 kGy irradiation dose. Moisture content

increased on storage. Among LDPE and paper bags, LDPE was found to be

best in preventing the ingress of moisture.

Effect of irradiation and packaging material was found to be non significant

on reducing sugars and sucrose content. Reducing sugars were increased on

storage where as sucrose content was found to decrease during storage.

No bacterial and yeast and mold growth was observed in irradiated samples.

Microbial population increased on storage. LDPE was found to be best in

preventing the growth of microorganism. Samples irradiated at 7.0kGy

showed least growth during storage. Jaggery samples stored in LDPE

pouches irradiated at 7.0kGy was found to be best till the end of storage

period i.e. 90 days.

Irradiation and packaging material was found to have no significant effect

on organoleptic properties. Also during storage no significant differences

were observed in scores.

Jaggery packed in LDPE pouches was found to be best till the end of storage

period. After 90 days of storage jaggery contained 93.15 % of

carbohydrates, 4.325mg of iron, 10.98 mg of calcium and 4.34mg of

phosphorus in 100gm of jaggery.

From the present study it was observed that shelf life of sugarcane juice can

be increased upto 60 days at room temperature and upto 90 days at low

temperature storage. Irradiation has further contributed in preservation of

juice. Among the three packaging materials i.e. glass, PET and LDPE; both

108

glass and PET were found to be best in increasing the shelf life of juice,

without affecting its physico - chemical, nutritional and sensory properties.

Jaggery can also be stored upto 90 days in LDPE pouches without having

much affect on its physico-chemical, nutritional and organoleptic properties.

Irradiation dose of 7.0kGy was found to be best in increasing the shelf life

of jaggery.

The present study conducted is a preliminary step for preservation of

sugarcane juice and jaggery. Consumers have become more conscious about food

safety therefore hurdle technology has arisen in response to number of

developments and therefore provides a framework for combining a number of

milder preservation techniques to achieve an enhanced level of product safety and

stability with minimum impact on the nutritional and sensory qualities. It can

therefore be recommended that in preservation of any food material, a combination

of hurdles, based on the physico-chemical and microbial susceptibility of the food

product need to be identified and employed.

109

LITERATURE CITED

Akpan, U.G and Kovo, A.S. 2005. Preservation of Passion Fruit Juice. Leonardo

Journal of Sciences issue. 7:17-22.

Alaka, O. O., Aina, J. O and Falade, K. O. 2003. Effect of storage conditions on the

chemical attributes of Ogbomoso mango juice. European Food Research

and Technology. 218(1): 79-82.

Alam, Z.E.B., Ullah Ihsan , Ahmad Anwar , Ali Khurshid and Ayub Mohammad.

2009. Grape Juice Preservation with Benzoate and Sorbate. Advances in

Food Sciences. 31(1):17-21.

Alex, L., Suresh, C. P., Kabir, J and Dhua, R. S. 2003. Litchi juice processing and

preservation. Advances in Plant Sciences. 16(1):215-218.

Alighourchi, H., Barzegar, M. and Abbasi, S. 2008. Effect of gamma irradiation on

the stability of anthocyanins and shelf-life of various pomegranate juices.

Food Chemistry. 110 (4):1036-1040.

AOAC. 2005 Official methods of analysis, Association of Official Analytical

Chemists, Washington, DC 18edition, 940.13.

AOAC. 1990. Official methods of analysis, Association of official analytical

chemists. Washington, D.C. 15th edition.

AOAC. 1965 Official Methods of Analysis, Association of Official Analytical

Chemists, Washington, D C 12th Edition 31.054, 22 :109.

110

Asokan, S. 2007. Sugarcane juice and jaggery as health drink and sweetner. Food

and Beverage News. F & B Specials: 1-3.

Azeredo, H.M.C.de., Araújo, F.B.S.de., Garruti, D.S. 2005. Ciênc. agrotec., Lavras.

29 (2):377-381.

Bindra, A.S.1997. Irradiation for safe durable foods. Indian Food Packer. 51(4):

54-57.

Bobadilla, M and Preston,T.R. 1981. The use of sodium benzoate and ammonium

hydroxide (aqueous -NH3) as preservative for sugar cane. Tropical Animal

Production. 6(4):345-349.

Bosse, B.B., Vaekumar, S., Sulochanamma and Ramalakshmi, K. 2006. Effect of

processing on quality of sugarcane juice. Proceedings of ICFOST,

Hyderabad, 16-17 November.

Brennan, J.G., 2006. Pulsed Electric Field Processing, Power Ultrasound and Other

Emerging Technologies. Wiley-VCH Verlag GmbH & Co. KGaA,

Weinheim. 201-232.

Chauhan,O.P., Dheer Singh., Tyagi, S.M., Balyan, D.K .2002. Studies on

Preservation of Sugarcane Juice. International Journal of Food Properties.

5 (1): 217 – 229.

Chumillas, M. R., Belissario,Y., Iguaz, A and Lopez, A. 2007. Quality and shelf life

of orange juice aseptically packaged in PET bottles. Journal of Food

Engineering. 79(1): 234-242.

111

Clara, C., Esteve, J.M and Frigloa, A. 2007. Effect of refrigerated storage on

ascorbic acid content of orange juice treated by pulsed electric fields and

thermal pasteurizations. European Food Research and Technology. 227 (2):

629-635.

Correa Neto, R. da S. Faria, J. de A. F. 2003. Chemical and enzyme changes in

pasteurizaded orange juice. Higiene Alimentar. 17(114/115): 60-67.

Ekanayake, S., Ranawana, C. K and Herath, H. M. R. P. C. 2004. A study on low

cost preservation of lime juice. Tropical Agriculturist. 155: 33-41.

El-Nemar, S.E., Ismail, I.A. and Askar, A. 1988. Aroma changes in mango juice

during processing and storage. Food Chemistry. 30( 4):269-275.

El-Sheikha A.F., Ribeyre, F., Larroque, M., Reynes ., M and Montet .,D. 2009.

Quality of physalis (physalis pubescens l.) juice packaged in glass bottles

and flexible laminated packs during storage at 5°C. African Journal of Food

Agriculture Nutrition and Development. 9(6): 1388- 1405.

Falade, K. O., Babalola, S. O., Akinyemi, S. O. S. and Ogunlade, A. A. 2004.

Degradation of quality attributes of sweetened Julie and Ogbomoso mango

juices during storage. European Food Research and Technology. 218(5) :

456-459.

Farooque, M. 1957. Role of microorganism in deterioration of gur in storage.

Indian Journal of Sugarcane Research and Development. 1(2): 69-71.

Farheen, F. 2004. Studies on the preparation of squash, nectar, RTS and juice

blends from watermelon fruits. MSc. Thesis submitted to Acharya

N.G.Ranga Agricultural University, Hyderabad, India.

112

Foley., D. M., Pickett, K., Varon, J., Lee, J., Min, D., B., Caporoso, F and Prakash,

A. 2002. Pasteurization of fresh orange juice using gamma irradiation-

Microbiological, flavour and sensory analysis. Journal of Food Science. 67

(4) : 1495-1501.

Frazier, C.W and Westhoff, C.D. 1995. Food Microbiology. Tata McGraw-Hill

Publishing Company Limited, New Delhi. 187-195.

Ghosh, A.K., Shrivastava, A.K. and Agnihotri, V.P. 1998. Production Technology

for lump sugar- Gur. Dayal publishing house. New Delhi. 148-162.

Goyle, A. and Ojha, P. 1998. Effect of storage on vitamin C, microbial load and

sensory attributes of orange juice. Journal of Food Science and Technology.

35(4):346-348.

HassanDar Gh, Yousuf Pargar Mohd. And Shah., G.H. 1992. Effect of processing

operations and heat treatment on physico-chemical characteristics and

microbiological load of apple juice concentrate. Indian Food Packer,

January – February, 46(1):45-50.

Jain, S., Sankhla , A., Dashora , P.K and Sankhla , A.K. 2003. Effect of

pasteurization, sterilization and storage condition on quality of sweet orange

( Mosambi) juice. Journal of Food Science and technology. 40 (6): 656-659.

Kad, V.P., Miss. Savane A.B., Kamble, B.D. and Khandetod, Y.P.2005. Food

Irradiation Boom to Agricultural processing. Beverage and Food World.

32(3): 42-44.

113

Kadam, U.S., Ghosh, S.B., De Strayo, Suprasanna, P., Devasagayam,T.P.A and

Bapat, V.A. 2008. Antioxidant activity in sugarcane juice and its protective

role against radiation induced damage, Food Chemistry. 106(3): 1154-1160.

Karthikeyan, J and Samipillai, S.S. 2010. Sugarcane in therapeutics. Journal of

Herbal Medicine and Toxicology. 4 (1):9-14.

Kaur, B., Singh, T and Kaur, H.1995. Recent advances in the processing and

preservation of sugarcane juice. Sugarcane: agro-industrial alternatives.

325-331.

Krishnakumar,T. and Devadas,C.T. 2006a. Microbiological changes during storage

of sugarcane juice in different packaging materials. Beverage and food

world. 33(10):82-83.

Krishnakumar,T. and Devadas,C.T.2006b. Quality changes in sugarcane juice by

delayed extraction and storage. Beverage and Food World. 33(2):76-78.

Kumar, P., Singh, S.K and Singh B. 2009. Standardization of Methodology for

the Preparation of Beverages and Studies during Preservation. Progressive

Agriculture. 9(1):34-36.

Kumar M.V. 2004. Effect of processing on quality characteristics of sapota pulp.

MSc. Thesis, Acharya N.G. Ranga Agricultural University, Hyderabad,

India.

Lee, J.W., Kim, J.K., Srinivasan, Periasamy., Jong-il Choi., Kim,J.H., Han,S.B.,

Kim, D.J. and Byun, M.W.2009. Effect of gamma irradiation on microbial

analysis, antioxidant activity, sugar content and color of ready-to-use

114

tamarind juice during storage. LWT - Food Science and Technology. 42

(1):101-105.

Leistner, L. 1999. Combined methods for food preservation. Handbook of Food

Preservation. Marcel Dekker, New York. 457-485.

Leistner, L. 2000. Basic aspects of food preservation by hurdle technology.

International Journal of Food Microbiology. 55(1-3):181-186.

Leistner, L., and Gorris, M. 1995. Food preservation by hurdle technology. Trends

in Food Sci. Technol. 6:4-9.

Lionnet, G.R.E. 1986. Post –harvest deterioration of whole stalk sugarcane.

Proceedings of the South African Sugar Technologists Association. June

1986: 52-57.

Madsen, L. R and Day, D. F. 2005. Mixed dithiocarbamates for the preservation of

sugar cane juice. International Sugar Journal. 107 (1282): 576-580.

Makhal, S. and Kanawjia, S.K. 2004. Food Irradiation: Myths, Philosophy and

Reality. Beverage and Food World. 31(1):19-25.

Mandal, D., Tudu, S., Mitra, S. R and De, G. C. 2006. Effect of common packaging

materials on keeping quality of sugarcane jaggery during monsoon season.

Sugar tech. 8(2&3):137-142.

Mandal, D., Tudu, S., Mitra, S. R and De, G. C. 2007a. Effect of initial moisture

content on keeping quality of sugarcane-jaggery stored in heat-sealed low

density poly ethylene (LDPE) packet during rainy season. Cooperative

Sugar. 38(9): 29-40.

115

Mandal, D., Tudu, S., Mitra, S. R. and De, G. C. 2007b. Studies on the effect of

class II preservatives on keeping quality of semi- solid jaggery (gur) stored

in edible oil canister during rainy season in sub tropical India. Sugar tech. 9

(2&3): 200-208.

Mao,L.C., Xu, Y,Q and Que, F. 2007. Maintaining the quality of sugarcane juice

with blanching and ascorbic acid. Food Chemistry. 104 (2):740-745.

Mitchell, G. E., Isaacs, A. R., Williams, D. J., McLauchlan, R. L., Nottingham, S.

M. and Hammerton, K. 1991. Low dose irradiation influence on yield and

quality of fruit juice. Journal of Food Science. 56 (6): 1628-1631.

Moreno, M.A., Perez, M.E.C., Gomes,C., Silva, P.F.D., Kim, J and Moreira, G.R.

2007. Jouranl of Food Process Engineering. 30: 436-457.

Muhammad, Ayub., Ullah, J., Muhammad, Ali and Zeb Alam. 2010. Evaluation of

strawberry juice preserved with chemical preservatives at refrigeration

temperature. International Journal of Nutrition and Metabolism. 2(2): 27-

32.

Nagalakshmi, A.V.D. 1995. Quality Analysis of selected fruit juices sold by street

vendor in Hyderabad. MSc. ( Home Science) thesis , Acharya N.G. Ranga

Agricultural University, Hyderabad, India.

Ohlsson, T., and N. Bengtsson. 2002. Minimal Processing Technologies in the Food

Industry, CRC Press LLC, New York. 175- 195.

116

Oliveira ,A.C.G., Seixas ,A.S.S., Sousa, C.P., Souza, C.W.A. 2006.

Microbiological evaluation of sugarcane juice sold at street stands and juice

handling conditions in São Carlos, São Paulo, Brazil .Cad. Saúde Pública,

Rio de Janeiro. 22(5):1111-1114.

Olivier and Garcia, A.C.2007. Effects of heat treatment and gamma radiation on the

characteristics of pure sugarcane juice and mixed with fruit juices. Ciênc.

Tecnol. Aliment. 27 (4):863-873.

Patil, J.P. and Adsule, P.G.1998. Studies on various quality parameters for grading

of jaggery. Indian Food Industry. 17(4):215-217.

Paul, T. 1997. Food Irradiation: A Need Based Technology. Indian Food Packer.

51(5): 53-55.

Periaym., D. R and Pilgrim., J. F. 1957. Hedonic scale method of measuring food

preferences. Food Technology. 11 (9): 9-14.

Potter, N.N and Hotchkiss, J.H. 1996. Food Science, 5th Edition,CBS Publishers

and Distributors , New Delhi. 478-513.

Puspha Singh, Shahi, H.N., Archna Suman and Jain, P.C. 2002. Sugarcane juice

concentrate- preparation, preservation and storage. Journal food science and

technology. 39(1):96-98.

Rao, P.V.K.J., Madhusweta Das and Das., S.K. 2007. Jaggery – A traditional

Indian Sweetner. Indian Journal of Traditional Knowledge. 6(1): 95-102.

Raghuramulu N, Madhavan NK, Kalyanasundaram S.1983. A manual of laboratory

techniques. National Institute of Nutrition ICMR. 1983; 142:319-320.

117

Ranganna, S. 1986. Hand book of Analysis and Quality control for fruit and

vegetable products. Tata McGraw Hill., New Delhi. 7-12.

Reddy, G.N.V.V. 2004. Studies on methods on extraction of sapota juice for

optimum yield and quality. MSc. Thesis submitted to Acharya N.G. Ranga

Agricultural University, Hyderabad, India.

Robert C. Soliva-Fortuny, Pedro Elez-Martínez, Mercè Sebastián-Calderó and Olga

Martín-Belloso. 2004. Effect of combined methods of preservation on the

naturally occurring microflora of avocado purée. Food Control. 15 (1):11-

17.

Roy, S.C. 1951. Gur monograph. Indian Institute of Sugar Tech. Kanpur.1-76.

Sachdeva, M., Mann, A.P.S and Batta, S.K. 2003. Multiple Forms of Soluble

Invertases in Sugarcane Juice: Kinetic and Thermodynamic Analysis. Sugar

tech. 5(1&2):31-35.

Sankhla, A., Kumari Vineta and Sankhla, A.K. 1999. Nutrional and microbial

quality of sugarcane juice. Journal of Dairying , Foods and Home Science

18(1): 27-31.

Singh, S., Dubey, A., Tiwari, L and Verma, A.K. 2009. Microbial profile of stored

jaggery: A traditional Indian sweetener. Sugar Tech. 11(2): 213-216.

Singh, I., Solomon, S., Shrivastava, A.K., Singh, R.K and Singh,J. 2006. Post –

harvest Quality Deterioration of Cane juice: Physio-biochemical Indicators.

Sugar Tech. 8(2&3):128-131.

118

Siswoyoa, T.A., Ika Oktavianawatia, Murdiyantob, D.U. and Bambang Sugihartoa.

2007. Changes of sucrose content and invertase activity during sugarcane

stem storage. Indonesian Journal of Agricultural Science 8(2):75-81.

Snecdor, G.W and Cohran, W.G. 1983. Statistical Methods. Oxford and IBH

publishing company.,New Delhi.217-235

Solomon,S. 2009. Post harvest deterioration of sugarcane. Sugar tech. 11(2): 109-

123.

Subbannayya, K., Bhatt, G.K., Shetty,S and Junu,V.G.2007. How Safe is Sugarcane

Juice? Indian Journal of Medical Microbiology. 25(1):73-74.

Sujatha, K., Thangaraj, T., Ramaswami, N. and Padmini, T. 2007. Standardization

and evaluation of preserved sugarcane juice blends with other fruit juices.

Indian Journal of Nutrition and Dietetics. 44(5):270-278.

Suryawanshi, A. B., Kirad, K. S., Phad, G. N and Patil, S. B. 2008. Standardization

of preservation method and their combination for safe storage of

pomegranate juice at room temperature. Asian Journal of Horticulture. 3(2):

395-399.

Swaminathan,M. 1991. Essential of foods and nutrition. Vol 11. Bangalore printing

and publishing Co.Ltd. 505.

Tambekar, D.H., Murhekar,S.M., Dhanorkar, D.V., Gulhane, P.B. and Dudhane,

M.N. 2009. Quality and safety of street vended fruit juices: a case study of

Amravati city, India. Journal of Applied Biosciences 14:782 - 787.

119

Thangavelu, S. 2006. Packing/wrapping materials and jaggery research - a review.

Cooperative Sugar. 37( 8): 29-40.

Thangavelu, S. 2007. Chemical composition of juice and jaggery (gur) in jaggery

production - a review. Cooperative Sugar.38(6) :41-58.

Thangavelu, S. 2008. Estimation of colour in juice, jaggery and sugar. Cooperative

Sugar. 40: 4, 49-56.

Titarmare, A., Dabholkar., P and Godbole., S. 2009. Bacteriological Analysis of

Street Vended Fresh Fruit and Vegetable Juices in Nagpur City, India.

Internet Journal of Food Safety.11:1-3.

Ulloa, J.A., Rosas-Ulloa, P., Flores, J.R., Ulloa-Rangel, B.E., Escalona, H. 2007.

Color behavior in jack fruit (Artocarpus heterophyllus) bulbs self stabilized

in glass jars by hurdle technology. Cienciay Tecnologia Alimentaria.

5(5):372-378.

Uppal, S. K. 2002. Storage of jaggery under low temperature for longer duration.

Sugar Tech. 4(¾):177-178.

Uppal, S.K., Sharma,S. and Sidhu, G. S. 2002. Effect of storage temperatures on

jaggery (gur) quality of different sugarcane varieties. Journal of Food

Science and Technology (Mysore). 39(5) 549-551.

Uppal, S. K., Sharma, S and Sidhu, G. S. 2004. Evaluation of storage systems of

jaggery under different storage temperatures. Journal of Research, Punjab

Agricultural University. 41(1)11-16.

120

Usha, R. , Nagaraju, Shankar, M. 2009. Impact of Storage on Quality of Jaggery

Produced in Mandya District Environment and Ecology [Environ. Ecol.] 27

(1A): 360-363.

Verma, R.S. 2004. Sugarcane Production Technology in India. International Book

Distributing Co. Chaman studio, Charbagh, Lucknow. 1-21.

Vijayanand, P., Nair, K.K.S and Narashimah, P. 2001. Preservation of pineapple,

mango and papaya chunks by hurdle technology. Journal of Food science.

38(1):26-31.

Walford, S.N. 1996.Composition of cane juice. Proc S Afr Sug Technol Ass.70:

265-266.

Yadira Rivera- Espinoza, Elsa Valdez –Lopez and Humberto Hernandez – Sanchez,

2005. Characterization of a wine like beverage obtained from sugarcane

juice. World journal of Microbiology & Biotechnology. 21 : 447-452.

Zanoni, B., Pagliarini, E., and Galli, A. 2005. Shelf-life of freshly squeezed orange

juice from organic farming methods. Industrie delle Bevande. 34 (195): 18-

20.

121

APPENDICES

APPENDIX - A

ESTIMATION OF MOISTURE CONTENT

Procedure:

1. The petridish with lid was weighed.

2. 10g or 10 ml of sample was weighed into the petridish and spread evenly for

uniform drying.

3. Oven was set at 100 to 1050C and the petridish with sample was placed

inside the oven with lid open for 15-17 hrs.

4. The petridish was cooled in a dessicator with lid open for 1-2 hrs.

5. The petridish with sample was weighed.

6. This was repeated for all samples till constant weight was achieved.

Calculations

(W2 - W1) – (W2 - W3) x 100 Moisture % = (W2 – W1)

Where,

W1 = Initial weight of petridish (g)

W2 = Weight of the petridish with sample before drying (g)

W3 = weight of the petridish with sample after drying (g)

122

APPENDIX - B

ESTIMATION OF REDUCING AND TOTAL SUGARS

Reagents used:

i. Fehlings solution(A): Dissolve 69.28g of copper Sulfate in water and

dilute to 1,000ml.

ii. Fehling solution(B): Dissolve 346g of Rochelle salt and 100g sodium

hydroxide in water and make upto 1,000ml.

iii. Methylene blue indicator: Dissolve 1g of methylene blue in 100ml of

water

iv. 45% Neutral lead acetate solution: Dissolve 225g of neutral lead acetate

in water and dilute to 500ml.

v. 22% Potassium oxalate solution: Dissolve 110g potassium oxalate in

water and dilute to 500ml.

Standard invert sugar solution:

Weigh accurately 9.5g of AR sucrose into a 1-litre volumetric flask. Add

100ml of water and 5ml of concentrated HCl. Allow to stand for 3 days at 20-250C

for inversion to take place, and then make up to mark with distilled water.

Preparation of sample:

25 ml or 25 gm of sample was transferred to 250 ml volumetric flask. Add

about 100ml of water and neutralize with 1N NaOH. Add 2ml of lead acetate

solution. Shake and let it stand for 10min. Add the necessary amount of potassium

oxalate solution to remove the excess of lead, make up to volume with water, and

filter.

123

Procedure for reducing sugars:

5ml Fehling ‘A’ + 5ml Fehling ‘B’ (150ml conical flask)

50ml H2O

Add little amount of sample from burette

Heat for 15 seconds

If colour remains blue add 2-3ml of sample from burette

Boil for few seconds.

Add 3 drops of methylene blue indicator

Titrate from burette till brick red colour comes.

Calculations:

Dilution Factor X Volume made up X 100 Reducing sugars = ------------------------------------------------------ Titre value X Weight or Volume of sample

Procedure for total sugars:

For total sugars, 50 ml of filtered sample was taken in a 250 ml conical flask

to which 50 ml water and 5 g citric acid was added. Boiled gently for 10 min to

complete the inversion of sucrose, then transferred to 250 ml volumetric flask and

neutralized with IN NaOH. The volume was made upto the mark and determined

the total sugars as invert sugars.

% sucrose = % total invert sugars - % reducing sugars x 0.95

Total sugars = % reducing sugars + % sucrose

124

APPENDIX -C

ESTIMATION OF ASCORBIC ACID

Reagents

i. 2,6-dichlorophenol indophenol dye solution: In a volumetric flask, 50 mg of

sodium salt of 2,6-dichlorophenol indophenol dye and 42 mg of sodium

bicarbonate were taken and dissolved in 100 ml hot distilled water. The volume

was made upto 200 ml with distilled water.

ii. Metaphosphoric acid (3%): Three grams of metaphosphoric acid was

dissolved in a small quantity of distilled water and the volume was made upto

100 ml or 30 g in 1000 ml of water.

iii. Standard ascorbic acid: 100 mg of L-ascorbic acid was dissolved in a small

quantity of 3 per cent metaphosphoric acid in 100 ml volumetric flask and

diluted to volume. From this 10 ml was taken in another 100 ml volumetric

flask and volume was made up with 3 per cent metaphosphoric acid (1 ml = 0.1

mg of ascorbic acid).

Standardization of dye

In a 100 ml conical flask, 5 ml of standard ascorbic acid solution was taken

and 5 ml of 3 per cent metaphosphoric acid was added. The dye solution was filled

in a burette and standard ascorbic acid solution was titrated. The end point was pink

colour which persisted for about 10 seconds. This was done in triplicates.

0.5 Dye factor = ------------

Titre value

Preparation of sample

In a 100 ml volumetric flask 10 ml of sample was taken and the volume was

made up with 3 per cent metaphosphoric acid.

125

Procedure

Five millilitre of 3 per cent metaphosphoric acid extract of the sample was

taken in a conical flask and titrated with standard dye. The end point was pink

colour which existed for 15 seconds. The titre value was noted.

Calculations :

Titre value x Dye factor x Volume made x 100 mg ascorbic acid per ml = --------------------------------------------------------------- Aliquot taken x Volume of sample taken

126

APPENDIX- D

ESTIMATION OF CARBOHYDRATES

Reagents:

i. 2.5 N HCl/Anthrone reagent: Dissolve 200mg anthrone in 100ml of ice cold

95% sulphuric acid. Prepared fresh before use.

ii. Standard glucose: Stock- dissolved to 100ml water.

iii. Working standard: 100mg of stock diluted to 10ml with distilled water.

Procedure:

100mg of the sample was weighed into boiling tube. It was hydrolyzed by

keeping it in a water bath for 3hrs with 5ml of 2.5N HCl and cooled to room

temperature. Then it was neutralized with solid sodium carbonate until the

effervescence ceased. The volume was made up to 100ml and centrifuged.

Supernatant was collected and 0.5 and 1ml aliquots were taken for analysis.

Calibration of standard curve

Working standard solution was taken in the volume of 0, 0.2, 0.4, 0.6, 0.8

and 1.0ml and the volume was made up to 1ml by adding distilled water. 4ml of

anthrone reagent was added to all the test tubes and were heated in a boiling water

bath for 8 minutes. They were cooled rapidly and the green to dark green colours

developed was read at 630nm. Samples were treated in the same way. The readings

obtained were plotted against different concentration of the standard and the

concentration of unknown was intercepted from the graph.

Calculations: mg. of glucose Amt. of carbohydrates (mg%)= X 100 Volume of test sample

127

APPENDIX – E

PREPARATION OF MINERAL SOLUTION

Procedure:

1. Moisten the ash with 0.5-1.0ml of glass distilled water and add 5.0ml of

conc. HCL

2. Evaporate the mixture to dryness on a boiling water bath

3. Add another 5ml concentrated HCL and evaporate to dryness

4. Add 4.0ml of conc. HCL and 4.0ml of glass distilled water, warm the

solution over a boiling water bath and filter in to al 50ml volumetric flask

using what man No.40 filter paper. Make up the volume to 50ml with glass

distilled water.

128

APPENDIX –F

ESTIMATION OF IRON

Reagents:

1. 2.2-dipyridyl (Bipyridyl) -Dissolve 10mg of 2.2-dipyridyl in double

distilled water and make up to 100ml.

2. Hydroxylamine hydrochloride-Dissolve 10g in double distilled water and

dilute to 100ml.

3. Acetate buffer- Dissolve 8.3g of anhydrous sodium acetate in 50ml water,

add 12ml of glacial acetic acid and make up to 100ml with water.

4. Iron standard solution- Dissolve 70.2mg of ferrous ammonium sulphate

in 5ml of 1:1HCL solution and make up the volume to 100ml.(iron

concentration-100µg/ml)

FLOW CHART

Take 0.2-1.0ml (20-100µg) of standard iron solution in five test tubes

Take 2.0ml of and 4.0ml of mineral solution in two separate test tubes

Add 1.0ml Hydroxylamine hydrochloride mix

Add 5.0ml acetate buffer and 2.0ml dipyridyle in to all the tubes

Make up the volume to 25ml by adding the required amount of double distilled

water.

Mix thoroughly

129

Read the absorbance at 510nm

Plot the graphs with concentration of iron on ‘x’ axis and O.D. values of ‘y’ axis

Observations:

S./Tube No.

Std. Iron(ml)

Conc. of Iron(µg)

Hydroxyl amine

HCL(ml)

Acetate buffer (ml)

Dipyridal (ml)

Double distilled

water O.D. value

1 - - 1.0 5.0 2.0 17.0 2 0.2 20 1.0 5.0 2.0 16.8 3 0.4 40 1.0 5.0 2.0 16.6 4 0.6 60 1.0 5.0 2.0 16.4 5 0.8 80 1.0 5.0 2.0 16.2 6 1.0 100 1.0 5.0 2.0 16.0

Mineral solution 7 2.0 - 1.0 5.0 2.0 15.0 8 4.0 - 1.0 5.0 2.0 13.0

Calculations

From the standard graph

2.0ml of mineral solution contains = µg of iron

50ml of mineral solution contains = µg of iron

….gm sample contains = µg of iron

100g sample contains = mg of iron/100g

50 100 Iron mg% = X x ------------- x ---------------------- 2 100/sample wt

X=sample concentration read from standard graph

130

APPENDIX – G

ESTIMATION OF CALCIUM

Reagents :

1. 0.01N potassium permanganate: Weigh 31.6mg of potassium

permanganate in to a 100ml volumetric flask, add distilled water and make

up the volume to 100ml.

2. 0.01N oxlic acid: Weigh 63mg of oxalic acid in to a 100ml volumetric

flask, add distilled water and make up the volume to 100ml.

3. 2N sulphuric acid: Take 5.6ml of concentrated sulphuric acid add distilled

water slowly to the acid and make up the volume to 100ml.

4. Standardize 0.01N potassium permanganate (5ml) against 0.01N oxalic acid

using 2ml of 2N sulphuric acid (calculate the normality and make necessary

corrections).

5. 0.1% methyl red indicator: Weigh and dissolve 10mg of methyl red

indicator in 10ml ethanol.

6. 20% ammonia: Dissolve 20ml of ammonia in distilled water and make up

to 100ml

7. 10% acetic acid: Dissolve 10ml of acetic acid in distilled water and make

up to 100ml

8. 6% ammonium oxalate: Weigh 6.0g ammonium oxalate, add distilled

water, dissolve and make 100ml (slightly warm the solution if necessary).

9. Wang’s wash: Mix32.7ml ethanol and 2.3ml ammonia solution.

131

FLOW CHART

Place 5ml of mineral solution in a 15ml centrifuge tube.

Add2.0ml water and a drop of methyl red indicator

Add ammonium hydroxide drop wise

The pink color disappears

Add acetic acid drop wise till faint pink color appears.

Shake the solution well

Add1.0ml of 6% ammonium oxalate

Mix thoroughly

Allow stand for one hour.

Centrifuge the tube, and invert on a blotting paper for 5 minutes.

132

Wash the precipitate with 4ml of wang’s wash solution

Repeat the centrifuging process.

Dissolve the precipitable in 2ml of 2N sulphuric acid

Heats the solution in water both up to 70-75C

Titrate against 0.01N potassium permanganate (while the solution is still hot).

A faint pink color appears as an end point.

Calculations:

Titre value of 1.0ml of 0.01N potassium permanganate =0.2004 mg of calcium

Calcium content = Total volume of mineral solution 100 Titre Value x 0.2004 x --------------------------------------- x ----------------------

Volume used for estimation weight of sample taken for ashing

133

APPENDIX – H

ESTIMATION OF PHOSPHORUS

Reagents:

i. Ammonium molybdate – 5 gm of ammonium molybdate is dissolved in 60 ml of

distilled water and 25 ml of sulphuric acid is diluted to 40 ml distilled water. Both

solutions are mixed.

ii. Hydroquinone solution – 0.5gm hydroquinone was dissolved in 100 ml of water

and drop of concentrated sulphuric acid was added to retard oxidation.

iii. Sodium Sulphate solution- 20 gm of sodium sulphate was dissolved in water and

then diluted to 100ml.

iv. Standard Phosphate – 0.0439 gm of pure dry KH2PO4 was dissolved in water

and diluted 100 ml which is stock standard solution.

v. Working standard phosphorus- 10 ml of stock solution taken in a 100ml

volumetric flask and make up the volume upto the mark with distilled water ( 1ml

contains 0.01mg phosphorus).

Procedure

Working Standard phosphorus

Water (ml)

Hydroquinone (ml)

Sodium sulphate

(ml) Ammonium molybdate O.D.

(µg) ml Blank 0.0 12 1 1 1

10 1.0 11 1 1 1 20 2.0 10 1 1 1 30 3.0 9 1 1 1 40 4.0 8 1 1 1 50 5.0 7 1 1 1

Sample 0.2 11.8 1 1 1

After adding all the reagents wait for half an hour till colour is developed completely. Read

the colour in spectrophotometer at 660nm.

Calculations Phosphorus content = 50 100 O.D. of sample x ------------ x ------------------------------ 2 weight of sample taken for ashing

134

APPENDIX - I

ESTIMATION OF VIABLE BACTERIAL COUNT

For estimating microbial population in different samples, dilution plate

method was followed. One ml or gram of sample was taken and added to 9ml of

sterile blank of water. Dilutions were shaked well for 10-15 minutes to obtain a

homogenized suspension of microorganism. This will give a dilution of 1:10 (10-1).

One ml from 10-1 dilutions was transferred to 9 ml of sterile blank water with a

sterile pipette, which gave a dilution of 10-2 . Then one ml of supernatant was

accurately pipetted using a micropipette into a test tube containing 9ml sterile saline

blank water that gave dilutions of 10-3. The processes were repeated upto 10-6

dilutions with the sterile water. Each time 1.0ml aliquot from 10-4, 10-5 and 10-6

dilutions were transferred to the sterile petri dishes for the enumeration of bacteria.

Plate count agar medium was used for estimating bacterial counts.

Calculations :

Number of colony forming units = mean number of Cfu’s x dilution factor (Cfu’s) per gm/ ml of sample quantity of sample on weight basis

135

APPENDIX - J

ESTIMATION OF VIABLE YEAST AND MOLD COUNT

One ml or gram of sample was taken and added to 9ml of sterile blank of

water. Dilutions were shaked well for 10-15 minutes to obtain a homogenized

suspension of microorganism. This will give a dilution of 1:10 (10-1). One ml from

10-1 dilutions was transferred to 9 ml of sterile blank water with a sterile pipette,

which gave a dilution of 10-2 . Then one ml of supernatant was accurately pipetted

using a micropipette into a test tube containing 9ml sterile saline blank water that

gave a dilutions of 10-3. The processes were repeated upto 10-6 dilutions with the

sterile water. Each time 1.0ml aliquot from 10-4, 10-5 and 10-6 dilutions were

transferred to the sterile petri dishes for the enumeration of bacteria. Plate dextrose

agar medium was used for estimating yeast and mold count

Calculations:

Number of colony forming units = mean number of Cfu’s x dilution factor

(Cfu’s) per gm/ ml of sample quantity of sample on weight basis

136

APPENDIX - K

SCORE CARD FOR SUGARCANE JUICE

Name:

Sample code:

Date :

Instructions:

1. You are presented with a sample of sugarcane juice. 2. You are required to evaluate the drink on 9 point hedonic scale on the basis

of colour, flavour, taste and overall acceptability. 3. Your comments and suggestions are most welcomed.

Sample code Attributes

Control 346 761

Colour & appearance Flavor Taste

Overall acceptability Hedionic scale 9- like extremely 8- like very much 7- like moderately 6- like slightly 5- neither like nor dislike 4- dislike slightly 3- dislike moderately 2- dislike very much 1- dislike extremely

Comments:

Signature of the judge

137

APPENDIX- L

SCORE CARD FOR JAGGERY

Name:

Date :

Instructions:

1. You are presented with a sample of jaggery.

2. You are required to evaluate the sample on 5 point hedonic scale on the

basis of colour and appearance, texture, taste and overall acceptability.

3. Your comments and suggestions are most welcomed.

Sample code Attributes

Control 346 761 123

Colour & Appearance

Texture Taste Overall acceptability

Hedionic scale

5- excellent

4- very good

3- good

2- fair

1 -poor

Comments:

Signature of the judge