results and discussion 4.1. chemical composition of barley flour

C H A P T E R - 4

RESULTS

AND

DISCUSSION

4.1 . Chemical Composition of Barley Flour

The barley grains were cleaned and ground through Udy

cyclone sample mill and the flour was tested for different

chemical characterist ics i .e. moisture, crude fat , crude protein,

crude fiber ash and NFE, soluble dietary fiber, insoluble dietary

fiber, total dietary fiber, pentosans and β -glucan contents.

The chemical characteristics of barley flour presented in

Table 4.1 indicated that the barley f lour contained 11.65%, 2.31%,

6.75%, 2.22% and 77.07% crude protein, crude fat , crude fiber, ash

and nitrogen free extract (NFE), respect ively. The results of the

present study for proximate composition of barley f lour are in line

with the earlier findings reported for Canadian varieties by (Li et

al . , 2001). Helm and Francisco (2004) also concluded that Brazilian

barley varieties showed crude protein content from 11.55 to

15.92%, crude fat 2.91 to 4.00%, ash 1.51 to 2.27% and crude fiber

5.95 to 7.12% and the result of the present study fall with in the

ranges reported by these scientists . Kiryluk et al . , (2000) have also

found crude protein content in hulled barley f lour as high as

15.83% and the ash content of 2.19% and these results also

Table 4.1 Chemical composition of barley flour

Component (%) on dry weight basis Crude protein 11.65±1.10

Crude fat 2.31±0.21

Crude fiber 6.75±0.59

Ash 2.22±0.19

NFE 77.07±5.50

Soluble dietary fiber 4.11± 0.39

Insoluble dietary fiber 7.37±0.65

Total dietary fiber 11.48±1.09

Pentosans 3.03±0.26

β-glucan 4.87±0.39

Support to the f indings of the present study for ash content but

differed for protein content which might be due to the variat ion in

genetic material as well as agronomic and environmental

condit ions experienced by the tested materia l.

The results regarding chemical composition of barley f lour

presented in Table 4.1 also substantiated that barley f lour

contained higher amounts of crude fiber (6.75%). The dietary f iber

of barley flour in the present study was found 4.11% soluble,

7.37% insoluble and 11.48% total dietary f iber. In ear lier studies

the variat ions in total dietary f iber, soluble dietary f iber and

insoluble dietary f iber content of bar ley f lour have been reported

ranging from 7.5 to 16.8%, 5 .6 to 6 .4%, and 1.9 to 10.4%,

respect ively in barley (Helm and Francisco, 2004; Vasanthan et a l . ,

2002) which are very close to resul ts found for various type of

total dietary fibers found in the present study. The results

presented in Table 4.1 further showed that barley f lour possessed

β -glucan 4 .87% and pentosans 3 .03% . The results for β -glucan and

pentosans content of bar ley f lour in the present study are within

the ranges reported by the research workers (Papageorgiou et a l . ,

2005 and Bhatty et al . , 1991). The β -g lucan is a so luble dietary f iber

component and is present in the highes t amounts in the endosperm of

barley.

4.2 . Analysis of β -glucan

The β -glucan is found to be the most abundant component of the

soluble dietary f ibre in oats and barley. I t is partial ly water

soluble and a l inear polysaccharide comprising only glucose units .

The resu l ts regarding β -glucan given in Table 4 .2

Table 4.2. Chemical Analysis of β-glucan

Component (%)

Moisture 3.55±0.29

Crude protein 9.96±0.89

Crude fat 1.17±0.08

Crude fiber 7.22±0.55

Ash 1.72±0.14

NFE 76.38±6.99

Soluble dietary fiber 75.05±5.88

Insoluble dietary fiber 10.25±1.02

Total dietary fiber 85.30±6.79

Pentosans 2.63±0.19

Starch 1.90±0.17

β-glucan 4.87±0.39

indicated that β -glucan possessed 9.96%, 1 .17%, 7.22%, 1.72% and

76.38% of crude protein, crude fat , crude f iber, ash and nitrogen

free extract (NFE), respect ively.

The present results regarding chemical composit ion β -glucan

are also in close agreement with the f indings reported by Bhatty

(1993) who demonstrated 3.3% ash content of β -glucan extracted

from barley bran. The ash content (Table 4.2) found in the present

study is a lso in close conformity with the previous work of

Burkus and Temel l i (2005) who reported ash content up to 4% in

β -glucan gum. The pentosans contents in the present study are

also inline with the results reported by Burkus and Temell i (2005).

The fat content in the β -glucan was found higher as

compared to reported by Fara j et al . , (2006) who found 0.05%

l ipids in high puri ty β -glucan concentrate which might be due to

less impurity of β -glucan extracted in the present study. The

contents of starch, soluble dietary f iber, insoluble dietary f iber

and total dietary f iber recorded during the present study are also

in consistent with the earl ier f indings of Faraj et al . , 2006) who

found variat ion from 0.4- 1.43% in starch content of β -glucan in

soluble dietary fiber (SDF) range from 71.81–75.75 % and the in

insoluble dietary f iber (IDF) content of β -glucan gum pellets in

the range of (8.77-17.3%). Symons and Brennan (2004) reported

range of 84.8 to 91.62% for total dietary fiber (TDF) of β -glucan

which also support the results obtained for this parameter in this

present study. Lambo et al . , (2005) reported that barley f iber

concentrate contained 79.8% of total dietary fiber which is very

close to the results obtained for total dietary f iber.

4.3 . Analysis of β -glucan beverage

4.3 .1. Color

4.3 .1.1 . L*-value

The stat ist ical results regarding L*-value measured through

colorimeter of di fferent beverages prepared by incorporat ion of β -

glucan at different levels are shown in Table 4.3 . I t is obvious

from the stat istical results that both treatments and storage

intervals exhibited significant effect on the L*-value of di fferent

beverages. The interact ion between the both the variables was

found to be non significant for this value of color.

The color index of different beverages shown in Table 4 .4

indicated that L*-value of beverages increased as the level of β -

glucan increased in the formulat ion of different beverages. The

results revealed significantly the highest L*-value (21.28) for

beverages of T6 contain ing 1 .0% β -glucan which decreased as the

β -glucan level was reduced in the beverages and 19.69 L*-value

was recorded for control beverage (without β -glucan). The results

(Table 4.4 ) further showed that beverage of T5 containing 0.8% β -

glucan and T6 beverage containing 1.0% β -glucan fal l statist ical ly

in the same group with respect to this color values. Similarly non

significant differences existed among beverages T2 (0.2% β -

glucan), T3 (0.4% β -glucan) and T4 (0.6% β -glucan) for L*-value

for color.

The ef fect of storage on the L*-value of different beverages

containing di fferent levels of β -glucan is shown in Table 4.4 .

Table 4.3 Mean sum of squares for color values (L, a, b) of stored β-glucan beverages

S.O.V. df L*-value a*-value b*-value

Treatments (T) 5 8.640** 48.371** 4.088**

Storage intervals (S) 6 16.546** 8.071** 17.226**

T x S 30 0.084NS 0.027NS 0.964NS

Error 84 0.052 0.048 0.164

** Highly Significant (P<0.01)

NS Non Significant

Table 4.4 Effect of treatments and storage intervals on the L*-value of stored β-glucan beverages

Means carrying same letters within a column or row do not differ significantly (P < 0.01)

Storage Intervals (days) Treatments

0 15 30 45 60 75 90 Mean

T1 (0% β-glucan) 21.60 19.97 19.63 19.50 19.33 18.97 18.80 19.69c

T2(0.2% β-glucan) 22.13 20.43 20.40 19.83 19.73 19.20 19.13 20.12b

T3(0.4% β-glucan) 22.40 20.73 20.20 19.93 19.73 19.50 19.33 20.26b

T4(0.6% β-glucan) 22.70 20.77 20.30 20.27 19.90 19.70 19.40 20.43b

T5(0.8% β-glucan) 23.37 21.40 21.17 21.20 20.70 21.20 19.80 21.26a

T6(1% β-glucan) 22.63 21.30 21.30 21.43 20.80 20.77 20.74 21.28a

Mean 22.47a 20.77b 20.50bc 20.36cd 20.03de 19.89ef 19.53f

It is evident from the results that L*-value of β-glucan beverages

declined significantly as a function of storage. The fresh beverage

possessed the highest L*-value (22.57) that reduced to 20.36 and

19.53 when tested after 45 and 90 days of storage.

It is important to note that with the increase of level of β-

glucan in the beverages affected significantly the L*-value, or

brightness of beverage. The present study indicated that

incorporation of β-glucan resulted in improvement of beverages

color as compared to the control beverage which was prepared by

the addition of 0.2%pectin without addition of β-glucan. More L*-

value by the addition of β-glucan obtained in the present study is

in consistent with the previous findings of Bensema (2000) who

found similar pattern for increasing in L*-value due to

supplementation of β-glucan. However, decline in L*-value during

storage may be attributed to the cloud loss in the beverage

containing with β-glucan as reported by Cortes et al . , (2008). The

decrease in L*-value was more persistent during first two weeks

but a bit stabilized after third week of storage. A small amount of

precipitate was visible at the bottom of the β-glucan beverage

which is due to insoluble protein and fiber components present in

the β-glucan at low levels. The precipitation of this material in case

of β-glucan supplemented beverage might be a cause of higher L*-

value for these treatments of beverage as reported by Temelli et al . ,

(2004) who prepared orange f lavoured barley β-glucan beverages

and showed changes during twelve weeks storage intervals.

4.3.1.2. a*-value

The analysis of variance pertaining to the a*-value of

different beverages prepared by incorporation of β -glucan at

different levels indicated that both treatments and storage

intervals showed significant effect on the a*-value of different

beverages (Table 4.3). However, the interact ion between both

variables was found non significantly different for a*-value.

The a*-values of different beverages presented in Table 4 .5

revealed that significant ly the highest a*-value (2.27) was

observed in beverage of T1 control beverage (without β -glucan)

while the lowest a*-value (1.28) was possessed by T4 (0 .4% β -

glucan). I t is obvious from the resul ts that a*-value of beverages

showed upword trend as the level of β -glucan increased in the

beverage formulat ions. This indicated decrease in the intensity of

red color in the beverages as a result of β -glucan addit ion in the

beverages. The results further substantiated that beverages of T4

(0.6% β -glucan) and T6 (1.0% β -glucan) fal l stat ist ical ly in the

same group with respect to a* color value.

The results for a*-value of dif ferent beverages prepared by

the incorporat ion of β -glucan shown in Table 4 .5 indicated that

a*-value of β -glucan beverages decreased significantly by

increasing the storage intervals . The beverage prepared fresh got

the highest a*-value (2 .90) which decl ined to 1.44 and 0.99 after 45

Table 4.5 Effect of treatments and storage intervals on the a*-value of stored β- glucan beverages


0 15 30 45 60 75 90 Means

T1 (0% β-glucan) 2.78 2.77 2.53 2.50 2.26 2.07 1.01 2.27a

T2(0.2% β-glucan) 2.67 1.43 1.20 1.20 1.13 1.10 1.07 1.40cd

T3(0.4% β-glucan) 2.99 1.55 1.39 1.30 1.10 0.99 0.98 1.47bc

T4(0.6% β-glucan) 2.80 1.33 1.27 1.00 0.90 0.83 0.83 1.28e

T5(0.8% β-glucan) 3.20 1.60 1.50 1.43 1.37 1.23 1.21 1.65b

T6(1% β-glucan) 3.00 1.30 1.26 1.18 1.03 0.85 0.84 1.35de

Means 2.90a 1.66b 1.53bc 1.44bcd 1.30cd 1.18d 0.99e


and 90 days of storage intervals respect ively. A decrease in the a*-

value indicated that beverage became less reddish intensity with

progress in storage periods. Moreover, a maximum change in the

red intensity was recorded during the f irst week of storage as

compared to the upcoming storage weeks. Sa ´ nchez-Moreno et a l . ,

(2005) have reported a decline in a*-value in pasteurize orange

juice during storage which supports to our findings.

In the present study a*-value decreased significant ly by

increasing the level of β -glucan in the beverages, which indicated

that increased β -glucan concentrat ion resulted in a less reddish

product as compared to the control beverage. The results of

present study are not incormity with the f indins of Bensema

(2000) who reported increasing trend of a-value in case of β -

glucan incorporat ion into barley β -glucan beverage with whey

protein Isolate and found shelfstabil i ty within twelve weeks

storage at refrigerat ion temperature. A decrease in a-value was

more persistent during f irst three weeks but a bit stabil ized after

third week.

4.3 .1.3 . b*-value

The statist ical results showed that b*-value of the color

index of beverages containing β -glucan at dif ferent levels was

significantly af fected due to treatments and storage intervals .

(Table 4.3 ) However, the interact ion between treatments and

storage intervals was found to be non significant for this at tribute

of color.

The beverages prepared from control treatment T1 with

0.2% pect in gave the highest b*-value (10.80) fol lowed by

Table 4.6 Effect of treatments and storage intervals on the b*-value of stored β-glucan beverages


0 15 30 45 60 75 90 Means

T1 (0% β-glucan) 10.50 10.77 11.00 10.70 10.80 10.80 11.00 10.80a

T2(0.2% β-glucan) 12.00 9.60 9.20 9.20 9.13 9.00 9.20 9.62c

T3(0.4% β-glucan) 12.40 9.80 9.60 9.40 9.30 9.40 9.00 9.84c

T4(0.6% β-glucan) 12.77 10.20 9.60 9.80 9.30 9.27 9.60 10.08bc

T5(0.8% β-glucan) 13.00 9.83 9.40 9.50 9.60 9.50 9.40 10.03bc

T6(1% β-glucan) 13.37 10.60 10.20 10.07 9.87 9.97 9.80 10.55ab

Means 12.34a 10.13b 9.83b 9.78b 9.67b 9.66b 9.67b


beverage T6 (1% β -glucan). The lowest b*-value was recorded in

beverage T2 (0.2% β -glucan). I t is obvious from the results that

incorporat ion of β -glucan in the beverage formulat ions exerted

significant response towards b*-value of beverages when added at

1%.

The results in Table 4 .6 also indicated that b*-value of

different beverages decreased significantly as a funct ion of

storage. The freshly prepared beverages got the highest b* -value

(12.34) which declined to 9 .76 after 45 days and to 9 .67 at the

expiry of the experiment (90days ) . The beverages containing β -

glucan yielded more yellowish color. I t is also obvious from Table

4.6 that decrease in b*-value of beverages was more persistent

with significantly reduced during f i rst two weeks of the storage

and beyond this period insignificant change in b* -value was

recorded up to expiry of the study i .e 90 days of storage. The

results of present study are in close agreement with the previous

f inding of Rodrigo et al . , (2003) who showed a significant

decrease of b*-value on pasteurized orange–carrot juices when

processed at 77 0C and stored at 100 C stable for a period of 32

days.

The addit ion of β -glucan at a level of 1% beverage showed

significant effect on b*-value. However, b* -value of dif ferent

beverages decreased as storage periods progressed. This decrease

was more during the f i rst two weeks of storage. The decline in b*-

value observed during the f i rst two weeks may be due to the

precipitat ion of insoluble material present in the beverages or

changes in the β -glucan colorant . Bensema (2000) substantiated

that b*-value of beverage was reduced from 12.4 to 9 .4 during the

refrigerated storage of 12 weeks, which is in l ine with the present

results as similar reducing trend of b*-value of beverages

observed in the present study. The values measured as L*, a* and

b* through colorimeter represent brightness, red to green and

yellow to blue color components, respect ively which decrease

significantly during the first two weeks of storage, for al l

beverages and stabil ized later on. The decrease in color values

during f irst two weeks may be attributed to precipitation of

insoluble material present in beverages or change in β -carotine

colorant as reported by Temell i et a l. , (2004) who also explained

that these precipitate are made from insoluble protein and fiber components

present in the β-glucan gum pellets at low levels during extraction procedure

4.3 .2. Viscosity

The stat ist ical results in Table 4.7 showed significant ef fect

of treatments on viscosity of beverages prepared from different

concentrat ions of β -glucan. However, the storage intervals and

interact ion of these two variables exhibited non signif icant effect

on viscosity of different beverages.

The results in Table 4 .8 showed that beverage prepared from

1% β -glucan incorporation (T6) possessed s ignificantly the highest

viscosity (21.75 mPa-s) followed by T5 beverage containing (0.8%

β -glucan). The lowest viscosity was recorded in T1 (0% β -glucan).

I t is a lso evident from the results in Table 4.8 that viscosity of

beverages increased progressively by increasing the level of β -

glucan in the formulat ion of beverages.

I t was observed that incorporat ion of β -glucan showed

improvement in viscosity of beverage which might be due to the

Table 4.7 Mean sum of squares for viscosity, specific gravity and total soluble solids (TSS) of stored beverages

S.O.V. df Viscosity Specific gravity TSS

Treatments (T) 5 1002.6629** 0.003148 NS 1.6948375**

Storage intervals (S) 6 0.6149915 NS 9.4524e-4 NS 0.5463508 NS

T x S 30 0.1087928NS 4.5238e-5 NS 0.001213NS

Error 84 0.4246667 0.0019 0.3711897

** Highly Significant (P<0.01) NS Non Significant

Table 4.8 Effect of treatments and storage intervals on the viscosity of stored β-glucan beverages


0 15 30 45 60 75 90 Means

T1 (0% β-glucan) 4.41 4.41 4.39 4.42 4.47 4.41 4.50 4.43f

T2(0.2% β-glucan) 6.96 6.97 6.98 7.02 7.01 7.03 7.07 7.01e

T3(0.4% β-glucan) 11.95 12.01 12.05 12.18 12.27 12.32 12.43 12.17d

T4(0.6% β-glucan) 16.07 16.14 16.28 16.40 16.51 16.60 16.62 16.37c

T5(0.8% β-glucan) 19.30 19.35 19.44 19.51 19.62 19.68 19.77 19.52b

T6(1% β-glucan) 21.30 21.41 21.52 21.60 21.72 21.80 22.87 21.75a

Means 13.33a 13.38a 13.44a 13.52a 13.60a 13.64a 13.88a


presence of polysaccharides (1→3, 1→4 β -glucan l inkages) . The

addition of β -glucan to water also results in the formation of a

viscous hydrocolloid solut ion (Dawkins and Nnanna, 1995;

Burkus, 1996) which might be one of the reasons towards increase

in the viscosity of beverages. The polysaccharide' s hydroxyl

groups are available to form hydrogen bonds with water which

makes the polymer water-soluble. Similarly, Glicksman (1982) also

demonstrated that presence of the polymers in solut ion creates a

random network, which increases the internal fr ict ion within the

solut ion. This results in an inhibit ion to internal f low and thus

increases the viscosity of the solut ion by the incorporat ion of β -

glucan in the beverage. Therefore, β -glucan offers various

applications l ike beverages where other thickeners, stabil izers, or

gell ing agents such as pectin, carrageenan, guar, and xanthan gum

may be replaced. The results of the present study are in l ine with

the previous f indings of Bensema (2000) who observed similar

increase in viscosi ty of beverage by the addit ion of β -glucan.

Thus i t may be inferred from the present results that the

thickening and stabil izat ion propert ies of barley β -glucan may be

advantageous in a beverage formulat ion. Temel l i et al . , (2004)

have reported a s l ight decrease in viscosity in some beverages

containing higher hydrocolloids content (0 .7%) and found stable

viscosity in al l other beverages. They also found stabil i ty of β -

glucan within the low pH in beverage formulat ions. These

f indings support the results found in the present study.

4.3 .3 Specific gravity

The stat ist ical analysis pertaining to the specific gravity of

different beverages prepared by incorporat ion of β -glucan at

different levels is shown in Table 4 .7. I t is evident from the

results that treatments, storage intervals and interact ion between

treatments and storage intervals showed non significant effect on

specif ic gravity of different beverages.

The speci f ic gravity of different beverages shown in Table

4.9 varied from 1.03 to 1.06 g/L among dif ferent beverages .

Mugula et al . , (2001) observed sl ight decrease in specif ic gravity

in pasteurized and unpasteurize togwa samples. These f indings

support the present study as non significant trend for this

parameter.

The study of Tiisekwa et al . , (2000) also showed small

variation in speci f ic gravity in Tanzanian fermented beverages

when stored at ambient temperature that also supports the

present study.

4.3 .4 Total Soluble Solids (TSS)

The stat istical results presented in Table 4.7 indicated that

total soluble solids of di fferent beverages were s ignificantly

affected by treatments; however, storage intervals and interact ion

between storage and treatments showed non significant effect on

TSS of di fferent beverages.

The results in Table 4.10 showed that the beverage

containing the highest level of β -glucan 1%, (T6) possessed the

highest contents of total soluble solids (10.42ºbrix) fol lowed by

T5 beverage conta ining 0 .8% β -glucan. The lowest total soluble

Table 4.9 Effect of treatments and storage intervals on the specific gravity of stored β-glucan beverages


0 15 30 45 60 75 90 Means

T1 (0% β-glucan) 1.02 1.02 1.02 1.02 1.03 1.03 1.04 1.03a

T2(0.2% β-glucan) 1.02 1.02 1.03 1.03 1.03 1.03 1.04 1.03a

T3(0.4% β-glucan) 1.03 1.03 1.03 1.03 1.04 1.04 1.05 1.04a

T4(0.6% β-glucan) 1.03 1.04 1.04 1.05 1.05 1.06 1.06 1.05a

T5(0.8% β-glucan) 1.04 1.04 1.05 1.05 1.05 1.06 1.06 1.05a

T6(1% β-glucan) 1.05 1.05 1.05 1.06 1.06 1.06 1.06 1.06a

Means 1.03a 1.03a 1.04a 1.04a 1.04a 1.05a 1.05a


Table 4.10 Effect of treatments and storage intervals on the total soluble solids of stored β-glucan beverages


0 15 30 45 60 75 90 Means

T1 (0% β-glucan) 9.51 9.54 9.60 9.68 9.75 9.86 9.94 9.70c

T2(0.2% β-glucan) 9.50 9.57 9.60 9.71 9.80 9.91 10.03 9.73c

T3(0.4% β-glucan) 9.72 9.77 9.81 9.88 9.96 10.04 10.13 9.90bc

T4(0.6% β-glucan) 9.89 9.92 9.95 10.06 10.16 10.26 10.37 10.09abc

T5(0.8% β-glucan) 10.01 10.05 10.09 10.17 10.27 10.39 10.48 10.21ab

T6(1% β-glucan) 10.19 10.26 10.31 10.42 10.52 10.60 10.67 10.42a

Means 9.80a 9.85a 9.89a 9.99a 10.08a 10.18a 10.27a


solids (9 .70ºbrix) were yielded by the beverage of T1 (0% β -

glucan). I t is obvious from the resul ts that total soluble solids of

beverages increased progressively by increasing the level of β -

glucan in beverage formulations.

The total soluble solids in different beverage did not differ

significantly as a funct ion of storage. The total soluble solids in

the freshly prepared β -glucan beverages were found 9.80 ºbrix

and total soluble solids 10.27ºbrix were recorded in the beverages

tested of the experiment (day 90) . The present study is supported

by the f indings of Mugula et a l . , (2001) who explained that TSS

decreased in unpasteurized and pasteurized beverage prepared

from sorghum. The f indings of present study are also in l ine with

the observations of Tiisekwa et al . , (2000). In other study, Akubor,

(2003) a lso repoted similar results in melon-banana beverage

during ambient temperature storage.

4.3 .5 pH

The results regarding pH of dif ferent β -glucan supplemented

beverages presented in Table 4.11.showed that pH of the

beverages was not affected by the treatments and interact ion

between treatments and storage intervals. The pH of different

beverage was significantly affected by the storage intervals.

The results regarding pH of the beverages given in Table 4.12

indicated non significant changes in pH due to different levels of

β -glucan supplementat ion.

Table 4.11 Mean sum of squares for pH, acidity and ascorbic acid content of stored β-glucan beverages

S.O.V. df pH Acidity Ascorbic acid

Treatments (T) 5 0.014* 0.084* 111.646

Storage intervals (S) 6 0.227** 0.008** 2447.942**

T x S 30 0.001NS 0.0001NS 13.116NS

Error 84 0.004 0.0002 30.928

** Highly Significant (P<0.01) NS Non Significant * Significant (P<0.01)

Table 4.12 Effect of treatments and storage intervals on the pH of stored β-glucan beverages


0 15 30 45 60 75 90 Means

T1 (0% β-glucan) 3.01 2.94 2.88 2.84 2.79 2.76 2.71 2.85a

T2(0.2% β-glucan) 2.97 2.91 2.85 2.80 2.74 2.71 2.68 2.81a

T3(0.4% β-glucan) 3.03 2.98 2.92 2.88 2.81 2.74 2.73 2.87a

T4(0.6% β-glucan) 3.03 2.96 2.93 2.87 2.83 2.76 2.74 2.87a

T5(0.8% β-glucan) 2.96 2.92 2.88 2.81 2.77 2.73 2.69 2.82a

T6(1% β-glucan) 3.05 3.01 2.88 2.84 2.81 2.73 2.65 2.85a

Means 3.01a 2.95ab 2.89bc 2.84cd 2.79cde 2.74de 2.70e


The results in Table 4.12 showed a significant effect of storage

intervals on the pH value of dif ferent beverages. The pH value of

freshly prepared beverages (0 day) was found significantly higher

3.01 which decreased to 2.70 when beverages tested after (90

days) . The pH values decreased significantly in al l the beverages

progressively throughout the storage period. The results of the

present study with respect to storage studies are in concordance

with the f indings of (Miguel e t al . 2004 and Falade et al . 2003) who

found a decreasing trend of pH in beverages during storage. Ziena

(2000) reported a gradual decline in pH and showed a percent

decrease in pH values range from 1.1% to 8.7% in refrigerated and

freeze l ime juices samples. High acid and low pH may be due to

production of acet ic acid and lact ic acid during storage. Such

types of changes in pH vales have been demonstrated by (Souci et

a l . , 1987; Kaanane et a l . , 1988; Mart in et al . , 1995). The results are

in consistent with the f indings of Akubor (2003) who also

reported drop in pH with storage period in melon-banana

beverage.

Fasoyiro et a l . , (2005) have founded a decrease in pH during

storage at 5 0 C. The Rosel le beverage containing three different

fruits (orange, apple and pineapple) was prepared. They found

decrease in pH from 3.54 to 2.80 during two weeks storage at

refrigerat ion temperature. The reduction in pH may be due to the

decomposit ion of fermentable polysaccharides i .e. β -glucan,

sucrose and high fructose corn syrup, which are present in

beverages. This sl ight decrease in pH is a funct ion of refrigerat ion

temperature storage, which slows down the rate of growth of

microorganisms during entire period of cold storage.

4.3 .6. Acidity

The statistical results regarding acidity of beverages

prepared from different levels of β-glucan presented in Table 4.11

indicated that acidity of beverages was significantly affected by the

storage intervals; however, treatments and interaction between

storage treatments showed non significant effect on the acidity of

different beverages.

The results in Table 4.13 further substantiated a non

significant effect due to different levels of β-glucan for different

beverages. The acidity of different beverages differed significantly

which was found 1.60 in the fresh beverages. The acidity was

increase linearly as the storage progressed which reaches 1.61 at

the end of experiment (three months) during storage period.

Alessandra et al . , (2004) also reported similar results which

supports the present findings for increase in acidity during

storage. The acidity increased significantly as a function of storage

of orange juice stored at 4 0C (1.37 g/100g) and at 10 0C

(1.36g/100g), after 4 and 3 weeks of storage, respect ively (Esteve et

al . , 2005).

During two weeks change in acidity was recorded from

1.90 to 2.25 in Roselle orange drink (Fasoyiro et al . , 2005) which

also supports the results of present study. The gradual increase in

acidity was due to refrigeration temperature. The decrease in pH

and increase in acidity during storage might be due to degradation

of sucrose, high fructose corn syrup and β -glucan by the action of

microorganisms which causes production of acids in beverages.

Table 4.13 Effect of treatments and storage intervals on the acidity of stored β-glucan beverages


0 15 30 45 60 75 90 Means

T1 (0% β-glucan) 1.40 1.46 1.47 1.50 1.52 1.54 1.60 1.50a

T2(0.2% β-glucan) 1.39 1.44 1.44 1.47 1.53 1.56 1.57 1.49a

T3(0.4% β-glucan) 1.44 1.46 1.53 1.54 1.56 1.59 1.62 1.53a

T4(0.6% β-glucan) 1.43 1.45 1.53 1.51 1.55 1.60 1.63 1.53a

T5(0.8% β-glucan) 1.41 1.44 1.48 1.53 1.56 1.61 1.60 1.52a

T6(1% β-glucan) 1.44 1.45 1.50 1.54 1.58 1.60 1.62 1.53a

Means 1.42a 1.45b 1.49c 1.52d 1.55e 1.58f 1.61g


4.3 .7 Ascorbic acid

The results regarding analysis of variance for ascorbic acid

content of d ifferent beverages prepared from different levels of β -

glucan have been presented in Table 4.11. The stat ist ical results

indicated that ascorbic acid content of different beverages was

affected signif icantly due to storage intervals but di ffered non

significantly due to treatments and interact ion between

treatments and storage intervals.

The results in Table 4 .12, showed non significant change in

ascorbic acid content , due to incorporat ion of β -glucan.

The ascorbic acid content was found higher a (294.06 mg/kg)

in fresh beverage which declined s ignificantly to 279.33 mg/kg

and 262.11 mg/kg after 45 and 90 days storage of beverages,

respect ively. I t is a lso evident from results that ascorbic acid

content of beverages decreased consistently as storage period

increased.

The f indings of the present study is in l ine with the work

reported by different researchers Crandall et al . , (1987) and Maria

et al . , (2003) who observed a significant loss of ascorbic acid (25 to

26%) during storage. In the present study the ascorbic acid

content decreased with the increase in storage periods. This

decrease might be due to the factors such as storage temperature,

oxidat ive enzymes, processing techniques, metal contamination,

and the presence of atmospheric oxygen in the head space.

Kabasakalis et al . , (2000) studied the ascorbic acid content of

commercia l fruit juices and observed that the loss of ascorbic acid

Table 4.14 Effect of treatments and storage intervals on the ascorbic acid contents of stored β-glucan beverages


0 15 30 45 60 75 90 Means

T1 (0% β-glucan) 293.33 290.33 283.33 280.67 276.67 270.67 264.00 279.86

T2(0.2% β-glucan) 297.33 291.33 283.00 279.00 271.33 263.33 257.67 277.57

T3(0.4% β-glucan) 291.67 287.33 286.00 281.00 271.33 267.67 261.00 278.00

T4(0.6% β-glucan) 293.00 288.67 282.67 273.67 271.67 264.00 259.00 276.10

T5(0.8% β-glucan) 296.00 294.00 289.67 283.00 275.00 273.00 268.67 282.76

T6(1% β-glucan) 293.00 287.67 283.00 278.67 274.00 269.00 262.33 278.24

Means 294.06a 289.89ab 284.61bc 279.33cd 273.33de 267.94ef 262.11f


was 29-41 % in commercial f ruit juices stored in closed container

at room temperature for 4 months . Similar results reported by

Otta (1984) who described gradual decrease in ascorbic acid at

refrigerat ion temperature due to prolong storage. Since in the

present study the beverages were stored at refrigerat ion

temperature, therefore the loss in ascorbic acid is in conformity

with the results of Otta (1984).

4.3.8 Reducing Sugars

The stat istical results regarding reducing sugars of beverages

presented in Table 4.15 indicated that the reducing sugars of

beverages were affected significantly by the storage intervals.

However, the treatments and the interaction between treatments

and storage intervals showed non significant effect on the reducing

sugars of different beverages.

The results for the reducing sugars of beverages prepared

from different treatments of β-glucan are presented in Table 4.16

which indicated that reducing sugars of beverages did not differed

significantly due to the incorporation of β-glucan in different

beverages.

The reducing sugars it increased significantly from 3.72 to

4.31 during 0 to 90 days of storage, respectively (Table 4.16). In

fresh beverage samples the reducing sugar content was found 3.72

mg which increased to 4.02 and 4.31 mg after 45 and 90 days of

storage, respectively. The results showed that reducing sugar

contents of beverage increased slowly in the first 15 days of

storage but increased consistently and rapidly as the storage

period increased indicating more production of reducing sugars in

the beverage samples in the later stages of storage periods.

Babsky et al . , (1986) studied storage effect on the composition

of clarified apple juice concentrate and reported that reducing

sugars increased from 0.286 to 0.329 moles per 100 grams and

sucrose decreased from 0.039 to 0 .015 moles per 100 grams after

111 days of storage. The reducing sugars were formed by the

inversion of sucrose hydrolysis effect of temperature as described

Table 4.15 Mean sum of squares for reducing, non reducing and total sugar content of stored β-glucan beverages

S.O.V. df Reducing Sugars Non Reducing Sugars Total sugars

Treatments (T) 5 0.0092NS 0.004NS 0.0087265NS

Storage intervals (S) 6 0.837** 0.357** 0.1086119 NS

T x S 30 0.001NS 0.001NS 8.954e-4 NS

Error 84 0.003 0.004 0.1528365


Table 4.16 Effect of treatments and storage intervals on the reducing sugars of stored β-glucan beverages


0 15 30 45 60 75 90 Means

T1 (0% β-glucan) 3.71 3.80 3.91 4.02 4.12 4.21 4.31 4.01

T2(0.2% β-glucan) 3.73 3.83 3.90 4.00 4.09 4.19 4.27 4.00

T3(0.4% β-glucan) 3.71 3.79 3.89 4.02 4.13 4.21 4.34 4.01

T4(0.6% β-glucan) 3.68 3.80 3.92 4.02 4.14 4.24 4.32 4.02

T5(0.8% β-glucan) 3.75 3.82 3.94 4.08 4.17 4.27 4.35 4.05

T6(1% β-glucan) 3.72 3.82 3.89 4.00 4.09 4.17 4.27 3.99

Means 3.72f 3.81ef 3.91de 4.02cd 4.12bc 4.22ab 4.31a


by Ranote and Bains (1982) and Stein et al . , (1986). Increases in

total sugars have also been observed by Godara and Pareek (1985)

in date palm juice during storage at room temperature.

The increase in reducing sugars have also been reported by a

number of research workers and the reason shown to increase in

this parameter has been due to conversion of non reducing sugars

to reducing sugars with the increased storage duration as reported

by Purthi et al . , (1984). He also reported an increase in reducing

sugars from 13.6 to 23.8 per cent and a decrease in non-reducing

sugars from 29.6 to 23.0 per cent at room temperature during

storage in juices of four commercial varieties of malta and orange.

The results are in close confirmatory with the finding of (Fuleki et

al . , 1994) who also reported increases in fructose from 4.12 to 6.76

and glucose from 0.70 to 2.27 in fruit juices during storage.

4.3.9 Non Reducing Sugars

Non reducing sugars of beverages stored for a period of

three months was not affected significantly by the treatments

(Table 4.15). The storage intervals showed significantly effect on

non reducing sugars of different beverages. The interaction

between treatments and storage intervals possessed non significant

effect on non reducing sugars of different beverages.

The contents of non reducing sugars of different beverages

were not significantly changed due to incorporation of different

levels of β -glucan.

The results in Table 4.17 revealed that non reducing sugars

decreased significantly as a function of storage. The non reducing

sugars were found significantly the highest content (5 .14) in fresh

Table 4.17 Effect of treatments and storage intervals on the non reducing sugars of stored β-glucan beverages


0 15 30 45 60 75 90 Means

T1 (0% β-glucan) 5.14 5.08 5.01 4.93 4.87 4.81 4.76 4.94a

T2(0.2% β-glucan) 5.15 5.09 5.04 4.97 4.90 4.83 4.78 4.97a

T3(0.4% β-glucan) 5.13 5.07 5.01 4.94 4.87 4.82 4.75 4.94a

T4(0.6% β-glucan) 5.17 5.11 5.03 4.96 4.90 4.82 4.77 4.97a

T5(0.8% β-glucan) 5.12 5.07 5.01 4.93 4.86 4.80 4.74 4.93a

T6(1% β-glucan) 5.13 5.06 5.02 4.93 4.86 4.81 4.76 4.94a

Means 5.14a 5.08ab 5.02bc 4.95cd 4.88de 4.82ef 4.76f


beverages which reduced to 4 .95 and 4 .76 after 45 and 90 days of

storage, respectively.

The f indings of the present study are well supported by

Singh et al . , (2007) who found that with increase in s torage t ime

non-reducing sugars decreased. The results are also in l ine with

the f indings of Chowdhury et a l . , (2008) who studied the six

months storage effect on the shelf l i fe of mixed juice and

significant decrease in non reducing sugars due to breakdown of

non reducing sugars (sucrose) with the react ion of acids.

4.3 .10. Total Sugars

The analysis of variance regarding total sugars of beverages

showed that total sugars were non significantly affected due to

treatments and storage intervals as well as the interact ion

between treatments and storage intervals (Table 4.15) .

The results for total sugars of di fferent beverages

presented in Table 4.18 substantiated that the total sugars content

in al l the treatments fe l l stat ist ical ly the same group and total

sugars remained unchanged by the incorporat ion of β -glucan in

the bevera ges . The tota l sugar cont ent of β -glucan supplemented

beverages s tored for a period of 3 months indicated also showed

non s ignif icant variat ion between the freshly prepared β -glucan

beverages and beverages evaluated af ter 90 days of storage

s tudies . The resul t s are wel l in agreement with the observations

Table 4.18 Effect of treatments and storage intervals on the total sugars of stored β-glucan beverages


0 15 30 45 60 75 90 Means

T1 (0% β-glucan) 8.85 8.88 8.92 8.95 8.99 9.02 9.07 8.95a

T2(0.2% β-glucan) 8.88 8.92 8.94 8.97 8.99 9.02 9.05 8.97a

T3(0.4% β-glucan) 8.84 8.86 8.90 8.96 9.00 9.03 9.09 8.95a

T4(0.6% β-glucan) 8.85 8.91 8.95 8.98 9.04 9.06 9.09 8.98a

T5(0.8% β-glucan) 8.87 8.89 8.95 9.01 9.03 9.07 9.09 8.99a

T6(1% β-glucan) 8.85 8.88 8.91 8.93 8.95 8.98 9.03 8.93a

Means 8.86a 8.89a 8.93a 8.97a 9.00a 9.03a 9.07a


of Chowdhury et a l . , (2008) who reported non significant increase

in total sugars up to six months storage at 280 C in juices.

4 .4 . Total Plate Count (TPC) of the beverage samples

The results in Table 4 .19 indicated that storage intervals

showed decline in total plate count (TPC) of β -glucan beverage.

The TPC value of freshly prepared beverage (0 day) was higher

1.29 × 104 - 4.46 × 10 4 which decreased to 1.17 × 104 - 4 .32 × 104 at

the end of the experimental study (90 day). Similar counts of TPC

have been reported for some juices and drinks in Egypt (Daw et a l .

1994). These results are also in agreement with those of Hancioglu

& Karapiner (1997) reported for Turkish boza beverages. The

contamination by these microorganisms in the beverages could

have occurred during processing and packaging, as most of the

people involved in the production and packaging do not take

necessary precautions. Contamination of food items may largely

be due to the presence of these organisms and their entrance into

the food or beverage as a result of poor hygiene and sanitat ion

condit ions (Bibek, 2001).

The results indicated that the TPC values decreased in al l

the beverages containing throughout the storage period. The

results of the present study with respect to storage period are in

consistent with the f indings of other researchers who reported

similar results for some t radit ional beverages and drinks (Daw et

a l . 1994). The TPC values decrease gradually during storage

intervals are this might be due to

Table 4.19 Effect of treatments and storage intervals on the total plate count (CFU/ml) of stored β-glucan beverages

Storage intervals (days) Treatments

0 15 30 45 60 75 90

T1 (0% β-glucan) 1.87 x 104 1.87 x 104 1.84 x 104 1.79 x 104 1.72 x 104 1.69 x 104 1.66 x 104

T2(0.2% β-glucan) 2.52 x 104 2.47 x 104 2.47x 104 2.39 x 104 2.39 x 104 2.33 x 104 2.33 x 104

T3(0.4% β-glucan) 3.66 x 104 3.63 x 104 3.60 x 104 3.57 x 104 3.57 x 104 3.52 x 104 3.48 x 104



T6(1% β-glucan) 1.29 x 104 1.29 x 104 1.25 x 104 1.23 x 104 1.19 x 104 1.19 x 104 1.17 x 104

increase in acidity which may cause a concomitant decrease in pH

value which may help to decrease TPC in the beverages (Kaanane

et al . , 1988; Mart in et al . , 1995). The total bacteria l counts obtained

in this study fal l between 1 .0 x 10 2 - 1 .0 x 105 CFU/ml which fal l

within the range of earl ier works done by Hatcher et a l . (1992).

4.5 . Sensory evaluation of β -glucan beverages

4.5 .1 Color

The analysis of variance pertaining to the color scores

assigned to dif ferent treatments of beverages by the panelist

indicated that color of beverages di ffered significantly due to the

treatments and storage intervals (Table 4.20) . However, the

interact ion between treatment and storage intervals showed non

significant ef fect on this sensory attribute.

The scores assigned to the color of different beverages

prepared by incorporat ion of β -glucan presented in Table 4.21

revealed that the beverage prepared by the incorporat ion of 0.2%

β -glucan got significantly the highest color scores (6.84) fol lowed

by the control beverage (0.2% pect in) . The panelists assigned the

lowest scores (4.94) to the color of T6 beverage (1.0% β -glucan). I t

is evident from the results (Table 4.21) that the beverages of

treatments T1 (control), T2 (0.2% β -glucan), T3 (0.4% β -glucan)

and T4 (0 .6% β -glucan) fel l stat ist ical ly in the same group with

respect to color scores. The results a lso indicated non significant

differences in color scores between beverages T5 (0.8% β -glucan)

and T6 (1 .0% β -glucan). The beverages containing β -glucan level

up to 0.6%, remained acceptable by the panel ists however, further

Table 4.20 Mean sum of squares for sensory evaluation of stored β-glucan beverages

S.O.V. df Color Flavor Sweetness Sourness Overall acceptability

Treatments (T) 5 24.686** 18.760** 18.873** 9.970** 34.811**

Storage intervals (S) 6 13.933** 27.297** 59.231** 22.338** 62.242**

T x S 30 0.526NS 0.283NS 0.169NS 0.987NS 0.125NS

Error 108 0.436 0.383 0.388 1.936 0.626

** Highly Significant (P<0.01)

NS Non Significant

Table 4.21 Effect of treatments and storage intervals on the color score of stored β-glucan beverages


0 15 30 45 60 75 90 Means

T1 (0% β-glucan) 7.4 7.2 7.0 6.8 6.8 6.0 5.2 6.63a

T2(0.2% β-glucan) 8.0 7.4 7.2 6.8 6.6 6.2 5.6 6.83a

T3(0.4% β-glucan) 7.8 7.2 7.0 7.0 6.8 5.4 4.8 6.57a

T4(0.6% β-glucan) 7.2 6.6 6.4 6.0 5.6 5.4 5.0 6.03a

T5(0.8% β-glucan) 5.8 5.2 5.0 4.6 5.0 4.8 4.6 5.00b

T6(1% β-glucan) 5.4 5.4 5.2 5.0 4.8 4.6 4.2 4.94b

Means 6.93a 6.50ab 6.30ab 6.03bc 5.93bc 5.40cd 4.90d


increase in the β -glucan level in beverages resulted decrease in

assigning scores to color. It is obvious that freshly prepared β -

glucan beverage got maximum scores for color (6 .93) which

reduced to 4.90 scores when evaluated at the end of the

experiment (90 days). The results showed that the panelists l iked

more the color of fresh beverages and this l iking reduced of

beverages stored (Table 4.21) .

Colour of any food product is an important criter ion for the

acceptabil ity of any food product . I t is one of the characterist ics

perceived by the senses and a mean for the rapid identif icat ion

and ult imately governs the acceptance or rejection of the food

product . The resul ts obtained in the present study for color score

are in l ine with the findings of Anjum et a l . , (2006) who observed

significant ef fect (p < 0 .001) on color parameters during different

storage conditions. Thus the beverages of different treatments got

significant variat ion in getting score for their color yet the score

assigned to the color after 90 days under refrigerated storage

remained acceptable. The change in color parameter may be due to

the mail lard react ion between reducing sugars and amino acids

(Gonzalez & Leeson, 2000). The results are in close agreement

with the f indings of Granzer (1982) who also reported similar

results for color of beverages at different storage periods.

4.5 .2 Flavor

The stat istical results for the scores assigned to f lavor of

beverages prepared from dif ferent β -glucan levels indicated that

f lavor score varied significantly due to dif ferences (β -glucan

levels) in t reatments as well as storage intervals (Table 4 .20) . The

interact ion between treatments and storage intervals showed non

significant effect on the scores given to f lavor of different

beverage.

The panelists assigned the significantly highest scores to the

f lavour of beverages containing 0 .4% β -glucan (T3) (Table 4.22) .

However, the beverage t reatment T6 (1.0% β -glucan) was ranked

at the bottom for f lavor scores (5.86) by the panelists. Th e

beverages containing 0.6% β -glucan and control (T1) got

stat ist ical ly similar scores for f lavour. The beverages containing

more than 0.6% β -glucan got lower scores for f lavor.

The ef fect of storage on the f lavor of beverages stored for a

period of three months showed that there was significant decrease

in assigning the scores to the f lavour beverages as a funct ion of

storage. The fresh beverages got significantly the highest scores

(8.33) while the beverages tested af ter 90 days storage got the

lowest score (5.10) by the panelists. I t is evident from the results

(Table 4.22) that scores assigned to f lavor of beverages decreased

as storage progressed three months.

A decrease in the scores assigned to f lavor of dif ferent

beverages may be attributed to the increase in acidity of beverage

which noticed during storage as reported in the earl ier section.

This increase in acidity may enhance the sourness and will

Table 4.22 Effect of treatments and storage intervals on the flavor score of stored β-glucan beverages


0 15 30 45 60 75 90 Means

T1 8.6 8.2 7.6 7.4 7.4 6.2 5.6 7.29ab

T2 8.6 8.4 7.8 7.4 7.2 6.6 5.6 7.37ab

T3 9.2 8.6 8.0 7.2 7.4 6.4 6.0 7.54a

T4 8.0 7.6 6.8 6.2 6.4 6.0 5.2 6.60bc

T5 7.0 6.8 6.4 5.8 5.8 5.6 4.6 6.00c

T6 7.2 6.6 6.0 5.4 5.6 5.2 5.0 5.86c

Means 8.10a 7.70ab 7.10bc 6.57cd 6.63cd 6.00de 5.33e


depress the f lavor of beverage with the passage of t ime during

storage.

A gradual decrease in f lavor, during storage may also be due

to degradation of f lavour due to storage of product at refrigerator

temperature and due to heat treatment applied during processing

and such reasons for decrease in f lavor have been reported by

Pruthi et a l . , (1981), Hassan (1976) . The change in f lavour as a

funct ion of storage may be due to the degradation of ascorbic acid

and furfural production (Shimoda & Osaj ima, 1981; Perez & Sanz,

2001)

The product ’s physico-chemical changes may alter flavor

during storage. The present study is wel l supported by the results

of Anjum et a l . , (2004) who described that effect of process heat

treatment and storage temperature are well correlated with the

production of of f f lavoring compounds due to browning react ion

and furfural production.

4.5 .3 Sweetness

The scores assigned to sweetness of di fferent beverages

differed significantly among treatments and storage intervals

(Table 4 .20) . However, the interact ion between treatments and

storage intervals showed non significant effect on this sensory

attribute.

The scores assigned to sweetness of different beverages in

Table 4 .23 revealed that the control beverage containing 0.2%

pect in got the highest scores for sweetness (6 .74) fol lowed the

beverage 0 .2% β -glucan. The beveraged of T6 containing 1.0% β -

glucan got the lowest scores (5.03) for sweetness. The beverage T1

(cont rol ) and T2 (0 .2% β -glucan) were place stat ist ical ly at same

level for scores given to sweetness . Non significant differences

existed for sweetness score between beverages of T5 (0 .8% β -

glucan) and T6 (1 .0% β -glucan). The results a lso demonstrated

that the beverages containing β -glucan up to 0.6% got acceptable

scores; however, further increase in addition of β -glucan levels in

the beverages got lower scores by the panelists.

The results a lso indicated that fresh beverages got higher

scores (7.00) which were reduced to 5.70 scores when evaluated

after 45 days of storage and to 5.07 scores tested after 90 days of

storage. The results of the present study showed that as the

storage time increase the sweetness score decreased.These

observations are wel l supported by the f indings of Esteve et a l . ,

(2005) and Fasoyiro et al . , (2005) who found that during storage

period pH decreases and acidity increases of juices and drinks,

due to the degradation of carbohydrates by the act ion of

microorganisms.

Table 4.23 Effect of treatments and storage intervals on the sweetness score of stored β-glucan beverages


0 15 30 45 60 75 90 Means

T1 (0% β-glucan) 8.0 7.8 7.2 6.6 6.0 6.0 5.6 6.74a

T2(0.2% β-glucan) 8.0 7.4 7.0 6.8 6.0 5.8 5.8 6.69a

T3(0.4% β-glucan) 7.2 7.0 6.2 5.8 5.6 6.0 5.4 6.17ab

T4(0.6% β-glucan) 6.8 6.6 6.0 5.4 5.6 5.8 5.0 5.89b

T5(0.8% β-glucan) 5.8 5.6 5.0 4.6 5.0 5.2 4.6 5.11c

T6(1% β-glucan) 6.2 5.6 5.4 5.0 5.0 4.0 4.0 5.03c

Means 7.00a 6.67ab 6.13bc 5.70cd 5.53cd 5.47cd 5.07d


4.5 .4 Sourness

The stat ist ical results for the scores given to sourness of

beverages prepared by different levels of β -glucan (Table 4.20)

indicated that sourness scores varied significantly due to

differences in treatments as well as storage intervals . The

interact ion between treatments and storage intervals showed non

significant effect on the scores given to sourness of different

beverages.

The scores assigned to the sourness of di fferent beverages

given in Table 4.24 revealed that the highest scores (6 .43) were

given to beverages of control treatment (T1) fol lowed by beverage

of T2 (0 .2% β -glucan) but non significant differences existed

between these two beverages. The beverage of treatment T6 (1.0%

β -glucan) got the lowest scores (5.11) for sourness. The beverage

containing 0 .6% β -glucan and control beverage got statist ical ly

similar scores. The incorporat ion of β -glucan more than 0.6%

showed a declining trend in gett ing the scores for the sourness.

The fresh beverages got the highest scores (6.97) for

sourness while the beverages tested at the expiry of s tudy i .e 90

days of storage got the significantly lowest scores for sourness

(4.60) . I t is evident from the results (Table 4.24) that scores given

to sourness of beverages decreased l inearly throughout the

storage period of three months.

The present study indicated that control beverage was

sl ightly sourer than the beverages containing different level of β -

glucan, but the differences in scores (pect in) of sourness were not

Table 4.24 Effect of treatments and storage intervals on the sourness score of stored β-glucan beverages


0 15 30 45 60 75 90 Means

T1 (0% β-glucan) 7.4 7.2 7.0 6.6 6.4 5.6 4.8 6.43a

T2(0.2% β-glucan) 7.2 7.0 7.0 6.6 6.4 5.6 5.0 6.40a

T3(0.4% β-glucan) 7.6 7.2 7.2 6.8 6.2 5.0 4.6 6.37a

T4(0.6% β-glucan) 7.0 6.8 6.8 6.4 6.0 5.4 4.6 6.14a

T5(0.8% β-glucan) 6.4 6.2 5.8 5.6 5.0 5.0 4.6 5.51b

T6(1% β-glucan) 6.2 5.8 5.6 5.2 4.0 5.0 4.0 5.11b

Means 6.97a 6.70a 6.57a 6.20ab 5.67ab 5.27ab 4.60b


s ignificant with beverages containing up to 0 .6% β -glucan. This

indicated that β -glucan does not contribute to beverage sourness

intensity. However, there was a sl ight decl ine in sourness

intensity in the beverage with β -glucan beyond 0.6%. Bensema

(2000) who also observed that addit ion of β -glucan may contribute

towards sl ight alkaline environment which reduces the sourness.

The results of the present study are also in agreement with the

f indings of Pangborn et a l . , (1973) who showed that sourness

decl ined by increasing the hydrocolloid concentration in the

beverages. The sensory evaluation of beverages regarding

sourness with storage got lower scores. The decrease in pH may

cause increase in acidity as a funct ion of storage which made the

beverage sourer. The results obtained from the present study are

in l ine with the f indings of Fasoyiro et a l . , (2005) and Akubor

(2003) who recorded sl ight increase in acidity during refrigerat ion

storage of Roselle orange drink. An increase in acidity resulted in

sourness in beverages.

4.5 .5 Overall Acceptability

The stat ist ical results for the score given to overall

acceptabil ity of beverages (Table 4.20) indicated that treatments

and storage intervals signif icantly affected the overal l

acceptabil ity scores. The interact ion between treatments and

storage intervals were found non s ignificant for overall

acceptabil ity scores.

The beverage prepared from the control treatment (T2) got

the highest overall acceptibil i ty scores (7.31) fol lowed by

beverage of T1 (0.2% pect in) but both these beverages possessed

non significant di fferences for overall acceptibil i ty scores. The

beverages of T3 (0 .4% β -glucan) and T4 (0 .6% β -glucan) treatments

got stat ist ical ly overall acceptabil i ty scores. The beverages of

treatments T5 (0 .8% β -glucan) and T6 (1% β -glucan) got the lowest

scores (5.11) by the panelists for overall acceptabil i ty scores. I t is

obvious from the results (Table 4 .25) that overall acceptabil i ty

scores got by beverages containing up to 0 .6% β -glucan

incorporat ion and control got stat ist ical ly similar scores. The

beverages contain ing more than 0.6% β -glucan got lower scores

for overall acceptabil i ty.

The scores for overall acceptabili ty of beverages decreased

during storage. The fresh beverages got the highest scores (7.37)

while the beverages tested after 90 days of storage got the lowest

overall acceptabil i ty scores.

The β -glucan has been found to be stable within the acidic

environment of an orange-flavored beverage, during processing

and refrigerated s torage. β -glucan's abil i ty to increase viscosity

upon addit ion to water makes i t an excellent thickener for

beverage applicat ions. These characterist ics provided more appeal

to the panel ists for making the decis ion about the overall

acceptabil i ty of beverages. The resul ts of the present study are in

l ine with the f indings of Renuka et a l . , (2009) who prepared fruit

juice beverages with fort if ied fructo-oligosaccharide and noted

the quality characterist ics with six months storage period. There

was negligible change in overall quality that ranges from 9.0 to

6.0 for different beverages at refrigerat ion temperature with

references to hedonic scale evaluation.

Table 4.25 Effect of treatments and storage intervals on the overall acceptability score of stored β-glucan beverages


0 15 30 45 60 75 90 Means

T1 (0% β-glucan) 8.4 8.4 8.0 7.2 7.2 6.2 5.4 7.26a

T2(0.2% β-glucan) 8.2 8.2 7.6 7.4 7.2 6.6 6.0 7.31a

T3(0.4% β-glucan) 8.0 8.0 7.4 7.0 7.0 6.2 5.4 7.00a

T4(0.6% β-glucan) 7.2 7.2 6.8 6.6 6.4 5.8 5.0 6.43a

T5(0.8% β-glucan) 6.2 6.2 6.0 5.4 5.4 4.4 4.0 5.37b

T6(1% β-glucan) 6.2 6.2 6.0 5.6 5.0 4.4 4.2 5.37b

Means 7.37a 7.37a 6.97ab 6.53abc 6.37bc 5.60cd 5.00d


Selection of best t reatments

After sensory evaluation best treatments were selected for

further studies. The beverages containing dif ferent levels of β -

glucan, gett ing maximum scores by the judges during entire

storage period were selected. Three best beverages were selected

for eff icacy study containing 0 .2, 0 .4 and 0.6% β -glucan levels

along with control beverage containing 0.2 % pect in, as i t is

commonly used in beverages preparation.

4.6 Efficacy studies of β -glucan beverages

4.6 .1 Total cholesterol

The stat ist ical results regarding total serum cholesterol of

healthy subjects fed with various levels of β -glucan supplemented

beverages are presented in Table 4.26. The results indicated that

total serum cholesterol was significantly af fected due to variat ion

in beverage formulat ions and study periods. The interact ion

between these both variables was found non significant for total

serum cholesterol .

I t is obvious from the results given in Table 4 .27 and

i l lustrated in Figure 4.1 that the highest concentrat ion of total

cholesterol (139.53 mg/dl) was observed in the control group

which was fed on beverage prepared without any addit ion of β -

glucan. The subject group fed on beverage containing 0 .6% β -

glucan (D) possessed the lowest content of total cholesterol

(132.30 mg/dl) in serum of healthy subjects at the end of study. I t

is evident from Figure 4 .1 that there was significant and

progressive decline in the total serum cholesterol by increasing

Table 4.26 Mean sum of squares for blood lipid profile of volunteers

S.O.V. df Total Cholesterol Triglycerides LDL HDL

Beverages (B) 3 107.368** 37.570** 55.266** 28.197**

Study Periods (S) 2 422.014** 398.238** 212.944** 63.649**

B x S 6 30.566** 12.210** 15.847** 7.837**

Error 24 0.069 0.031 0.010 0.012


2.10

2.97

6.73

8.26

1.45

2.76

5.174.56

0

1

2

3

4

5

6

7

8

9

% Decrease

Week2 Week3

Study Period

A

B

C

D

2.10

2.97

6.73

8.26

1.45

2.76

5.174.56

0

1

2

3

4

5

6

7

8

9

% Decrease

Week2 Week4

Study Period

A

B

C

D

Table 4.27 Effect of β-glucan supplemented beverage on serum total cholesterol

content (mg/dl) of healthy subjects

Study Periods Beverage

Base Line Week-2 Week-4 Means

A 142.20 139.21 137.19 139.53a

B 141.74 137.53 133.74 137.67b

C 141.98 132.42 125.57 133.32c

D 142.11 130.37 124.42 132.30d

Means 142.01a 134.88b 130.23c


Figure 4.1. % decrease in the serum total cholesterol level of subjects fed on

different beverages

A = Beverage supplemented with 0% β-glucan (control) B = Beverage supplemented with 0.2% β-glucan C = Beverage supplemented with 0.4% β-glucan

D = Beverage supplemented with 0.6% β-glucan

137.19

133.75132.46

125.57

142.20

139.21141.78

137.57

141.95142.1

124.42

130.35

115

120

125

130

135

140

145

Base Line Week-2 Week-4

Weeks

To

tal

Ch

ole

ster

ol

(mg

/dl)

A B C D

Figure 4.2 Effect of β-glucan beverage on Total Cholesterol (mg/dl) content of

healthy volunteers A = Beverage supplemented with 0% β-glucan (control) B = Beverage supplemented with 0.2% β-glucan C = Beverage supplemented with 0.4% β-glucan


the level of β-glucan in the beverage formulations. There was a

decrease in total cholesterol content when the subjects were fed on

beverages C (0.4% β-glucan) and D (0.6% β-glucan). The results in

Figure 4.2 also showed that total cholesterol of healthy subjects

decreased at a faster rate during first two weeks as compared to the

last two weeks of the experimental study. The highest decrease in

total cholesterol (8.26%) content was observed in the group of

subjects fed on 0.6% β-glucan supplemented beverage (D) followed

by the group fed on beverage C (0.4% β-glucan) and the lowest

decrease in the serum cholesterol was observed in the group fed on

control beverage (0% β-glucan) both when tested at week 2 and

week 4. However, Figure 4.2 also depicted that maximum decrease

in total cholesterol content was shown by the beverage C (0.4% β-

glucan) when subjects were tested after four weeks.

A significant decrease in the total serum cholesterol of test

subjects was found in the present study which might be due to

different factors including the presence of β-glucan, soluble dietary

fiber and tocopherol content of barley β-glucan supplemented in

beverage. It is well documented that β-glucan has the ability to

reduce the blood serum total cholesterol content of different

subjects (Uusitupa et al. 1992). β-glucan is a soluble dietary fiber

portion of barley and possess the ability to decrease the total

cholesterol. Ornish et al. (1998) have shown reduction in plasma

cholesterol concentrations due to contents of dietary fiber. Brown et

al. , (1999) also reported that 1g of soluble fiber can lower total

cholesterol by about 0.045mmol/L. It has been recommended by

FDA that at least 3 g/day of β-glucan from barley should be

consumed to achieve a clinically relevant reduction in serum total

cholesterol concentrations (FDA, 1996). Soluble dietary fibers may

increase the binding of bile acids in the intestinal lumen, which

leads to a decreased enterohepatic circulation of bile acids and a

subsequent increase in the hepatic conversion of cholesterol to bile

acids (Bell et al. , 1999). Another suggested mechanism is that the

increased viscosity of the food mass in the small intestine because of

soluble fibers leads to the formation of a thick unstirred water layer,

adjacent to the mucosa. This layer may act as a physical barrier to

reduce the absorption of nutrients and bile acids (Beer et al., 1995).

Thus these properties of β-glucan have shown a significant decline

in total cholesterol due to intake of different beverages containing

different levels of β-glucan.

4.6.2 Triglycerides

The analysis of variance showed significant effect of

functional beverages and study periods on triglyceride content of

adult subjects (Table 4.26). The interaction between functional

beverages and study periods was found non significant for this

biochemical parameter.

The results i l lustrated in Figure 4 .4 and Table 4 .28 indicated

the funct ional beverages showed dif ferent response towards level

of serum triglycerides in di fferent adult groups. I t is evident from

Figure 4.4 that level of serum triglyceride was higher in the

subject group fed on control beverage (0% β -glucan), while the

level of triglyceride content was recorded maximum in the group

fed on beverage D (0.6% β -glucan).I t is also obvious from Figure

4.3 that

3.694.47

10.4310.99

4.97

6.727.67 7.57

0

2

4

6

8

10

12

% Decrease

Week2 Week4

Study Period

A

B

C

D

3.694.47

10.4310.99

4.97

6.727.67 7.57

0

2

4

6

8

10

12

% Decrease

Week2 Week4

Study Period

A

B

C

D

3.694.47

10.4310.99

4.97

6.727.67 7.57

0

2

4

6

8

10

12

% Decrease

Week2 Week4

Study Period

A

B

C

D

3.694.47

10.4310.99

4.97

6.727.67 7.57

0

2

4

6

8

10

12

% Decrease

Week2 Week4

Study Period

A

B

C

D

Table 4.28 Effect of β-glucan supplemented beverage on serum Triglycerides content (mg/dl) of healthy subjects



A 86.68 83.48 79.33 83.16a

B 85.47 81.65 76.16 81.09b

C 87.47 78.35 72.34 79.39c

D 86.11 76.65 70.85 78.54d

Means 86.43a 80.28b 74.92c


Figure 4.3 % decrease in the serum triglycerides level of subjects fed on different

beverages



79.3376.16

72.34

86.68

83.4885.47

81.6578.35

87.4786.11

77.65

71.85

60

65

70

75

80

85

90


Weeks

Trig

lyce

ride

s (m

g/dl

)

A B C D

Figure 4.4 Effect of β-glucan beverage on Triglyceride (mg/dl) content of healthy

volunteers A = Beverage supplemented with 0% β-glucan (control) B = Beverage supplemented with 0.2% β-glucan C = Beverage supplemented with 0.4% β-glucan


reduction in the tr iglyceride contents increased by increasing the

level of β -glucan in different the beverages.

The triglyceride content of subjects fed on di fferent

funct ional beverages decreased at higher rate during the

beginning of days of the experiment . There was maximum

decrease in triglycer ide content (10.99%) in subject group fed on

the beverage D (0 .6% β -glucan) when tested after week-2 while

the lowest decrease in triglycerides was recorded in the group fed

on beverage A (control) . The rate of reduction in t riglyceride

content was at a lower rate after 2 weeks of storage study. The

beverage C (0.4% β -glucan) showed more pronounced ef fect on the

content of tr iglycerides during the last fortnight of the experiment

as compared to al l other beverages.

The results regarding triglycer ide contents presented in Table

4.28 indicated the triglyceride content of healthy subjects differed

significantly as a funct ion of storage.

The results of the present study are in agreement with the

f indings of Delaney et al . , (2003a) who found a decrease in serum

triglyceride content of rats as compared to control by

administration of β -glucan in the feed. The study demonstrated

that tr iglyceride content reduced progress ively as the level of β -

glucan increased in the beverage and the highest reduction was

achieved by the supplementat ion of 0 .6% β -glucan in the beverage

formulat ion. The decrease in triglyceride content may be

attributed to the level of β -glucan content has the abil i ty to

reduce triglycer ide content .

I t is evident from the previous studies that the level of

tr iglyceride content reduced by the β -glucan incorporation in

different food products Biorklund et a l . , (2005) observed changes

in serum lipids and reported a total reduction of 0 .14mmol/l with

a diet containing 5g β -glucan from oat for a period of f ive weeks

study. Similar decrease in triglycerides has been reported

observed by Naumann et a l . , (2006) who incorporated β -glucan in

to fruit drink and found a total 1 .26% decrease in subjects of β -

glucan group for a period of fives weeks. I t may be concluded

from the present study that by intake of β -glucan in beverage

formulat ion can help to reduce the triglycerides content in human

subjects to a signif icant level .

4.6 .3 Low Density Lipoproteins (LDL)

The stat ist ical results regarding LDL content of adult subjects

fed on beverages supplemented with various levels of β -glucan

are shown in Table 4.26. The results indicated that LDL was

affected significantly by the variat ion in beverage formulat ions as

wel l as study periods. The interaction between beverages and

study periods was found to be non significant for LDL content of

different subjects .

The highest concentrat ion of LDL (52.02 mg/dl) was

recorded in the subject group fed on beverage (control ) without

addition of β -glucan (Table 4 .29 and Fig. 4.6 ) . The subject group

fed on

4.33

7.54

14.8716.57

1.11

4.19

7.69 7.43

0

2

4

6

8

10

12

14

16

18

% Decrease

Week2 Week4

Study Period

A

B

C

D

Table 4.29 Effect of β-glucan supplemented beverage on serum LDL content (mg/dl) of healthy subjects



A 53.76 51.43 50.86 52.02a

B 53.45 49.42 47.35 50.07b

C 53.65 45.67 42.16 47.16c

D 53.88 44.95 41.61 46.81d

Means 53.68a 47.87b 45.50c


Figure 4.5 % decrease in the serum LDL level of subjects fed on different beverages



50.86

47.35

42.16

53.7651.4353.45

49.4245.67

53.6553.88

41.6144.95

30

35

40

45

50

55

60


Weeks

LD

L (

mg

/dl)

A B C D

Figure 4.6 Effect of β-glucan beverage on LDL (mg/dl) content of healthy



beverage containing 0 .6% β -glucan (D) exhibited the lowest

content of LDL (46.81 mg/dl) in serum of adult subjects . I t is

evident from Figure 4.6 that concentrat ion of LDL decreased

progressively by increasing the level of β -glucan in the beverages.

The level of LDL content declined at a faster rate in case of

beverages C (0.4% β -glucan) and D (0 .6% β -glucan) as compared

to control beverages (0% β -g lucan). The LDL concentrat ion

decreased at higher rate during f irst two weeks as compared to

the last two weeks of the experimental study. It is a lso evident

from Figure 4 .5 that at the end of two weeks of study period the

highest decrease in LDL (10.82%) content was observed in the

subjects group when the data for beverages pooled.

The decrease in LDL content was recorded at faster rate during

1s t two weeks of study. The beverage showed maximum response

towards decrease LDL content in the beginning of the study as

compared to the last weeks of the study period (Figure 4 .6) .

Braaten et a l . , (1994) have reported 10% decrease in LDL

cholesterol concentrat ions in hypercholesterolemic men and

women who consumed daily for 4 weeks 7 .2 g of oat gum

containing 5.8 g of β -glucan mixed with a noncarbonated drink or

with water. Kahlon and Chow (1997) a lso found similar results in

hyperl ipidaemic subjects fed on oat water-soluble gum. These

f indings are well in support of the present results in which a

decrease in LDL level by the intake of β -glucan in the funct ional

beverage formulat ions.

4.6 .4 High Density Lipoproteins (HDL)

The analysis of variance regarding serum HDL level of adult

subjects showed significant effect of beverages and study periods

on HDL content (Table 4.26) .The interact ion between beverages

and study periods was observed to be non significant for this HDL

content of serum.

The results i l lustrated in Figure 4 .8 and Table 4.30 showed a

variable response by di fferent functional beverages towards level

of HDL in dif ferent groups of people . The serum HDL content was

recorded h igher in the subjects fed on D beverage (0 .6% β -glucan),

while the lowest HDL content was recorded in the group fed on

control beverage (0% β -glucan) (Fig.4.8) . I t is a lso ev ident from

Figure 4 .7 that higher increase in level of tr iglyceride was

observed by the increasing level of β -glucan in the formulat ion of

different beverages.

The HDL content increased at a faster rate during f irs t two

weeks while the rate of increase was less at the end of the

experimental study. The highest increase in the HDL content was

observed in the group fed on the beverage D (0.6% β -glucan) when

tested at the end of week 2 while the lowest increase was

observed in the group consuming control beverage. The increase

in HDL content of test subjects was lower after fol lowing f irst two

weeks of study.

Week2Week4

1.35

5.32

9.9310.69

0.050.250.34 0.310

123456789

1011

% I

ncre

ase

Study Period

A

B

C

D

Table 4.30 Effect of β-glucan supplemented beverage on serum HDL content (mg/dl) of healthy subjects



A 62.37 63.21 63.24 62.61d

B 61.84 65.13 65.29 63.98c

C 62.06 68.22 68.45 66.08b

D 62.14 68.78 68.99 66.32a

Means 62.10c 66.34a 65.80b


Figure 4.7 % increase in the serum HDL level of subjects fed on different beverages



62.2461.84

64.97

62.37 63.21

65.1362.06

67.9568.22 68.03

62.14

68.78

58

60

62

64

66

68

70


Weeks

HD

L (

mg

/dl)

A B C D

Figure 4.8 Effect of β-glucan beverage on HDL (mg/dl) content of healthy



The study period showed a significant ef fect on the HDL

content of test subjects . The maximum increase in HDL was

observed in the f irst f i f teen days (two week) while the lower

response was observed following the next fi f teen days upto the

expiry of the experiment (Table 4.30) . The results of the present

study are well supported by Kalra and Jood (2000) who observed a

higher HDL content of rats with the consumption of barley β -

glucan gum as compared to control group of rats . The results f rom

such type of studies demonstrated that every 1% rise in HDL by

the ut i l izat ion of medicine, there is a 3% reduction chance in

coronary heart diseases (Frick e t a l . , 1987). The results of the

present study are also in l ine with the findings of Naumann et a l . ,

(2006) who incorporated β -glucan into fruit drink and observed

2.74 percent increase in HDL during f ive weeks study period in

human subjects. They suggested that in order to overcome and

reduce cardiovascular diseases, i t is better to use β -glucan in our

daily diet because low HDL heightened risk for heart disease. The

results of the present study showed that intake of β -glucan in

beverage significantly reduced serum cholesterol and LDL, while

significantly increased HDL level . This study demonstrates that

beverage containing β-glucan can help to reduce risk of coronary

heart disease.

4.6 .5 Blood Glucose concentarion

The stat ist ical results regarding blood glucose level of adult

volunteers showed significant ef fect of β -glucan treatment ,

feeding intervals and study periods on blood glucose level (Table

4.32) . The interact ive ef fect of intervals and treatments also

possessed significant effect on the blood glucose of adult

volunteers subjects . All interact ions among these three variables

were found to be non significant for blood glucose level .

The results presented in Table 4.33 showed different

response towards level of blood glucose by different beverages. I t

is evident from the results (Table 4.32) that higher blood glucose

level (100.17 mg/dl) was observed in the adults fed on control

beverage i .e. A (0% β -glucan), fol lowed by beverage B (0.2% β -

glucan). The lowest blood glucose content (97.55 mg/dl) was

recorded in the group fed with D beverage (0.6% β -glucan). i t i s

also obvious from the results shown in Figure 4.9 that higher

reduction in blood glucose level of adult subjects was observed by

increasing the level of β -glucan in the beverage formulat ion. The

level of blood glucose increased in al l beverages t i l l f irst hour of

study and then s tarted declining after one hour. The results

indicated (Table 4 .33) that rate of reduction in the concentrat ion

of blood glucose was significantly di fferent among different

beverages. The adult subjects fed on beverages D (0 .6% β -glucan

beverage) showed higher reduction in blood glucose level than

groups fed on al l other treatments. The blood glucose level of the

adults fed with beverage D reduced from 93.39 mg/dl to 81.35

mg/dl from 0 to 60 minutes of the study.

The blood glucose level varied significantly during dif ferent

study periods. I t is evident from Table 4.32 that blood glucose

was found the highest (95 .10 mg/dl) at the beginning of the study

(0 day) when the data for beverage and study period were pooled

but i t reduced significantly from 93.24 mg/dl to 91.92 mg/dl

Table 4.31 Mean sum of squares for blood glucose contents of volunteers

SOV df MSS Intervals (A) 5 1292.9373** Diets (B) 3 1906.9863** Days (C) 2 171.78671** A x B 15 94.341233** A x C 10 2.6435555NS B x C 6 1.5218384 NS A x B x C 30 1.3125518 NS Error 144 18.758931 Total 215

Table 4.32 Effect of β -glucan beverage on blood glucose (mg/dl)content

with different time intervals

Beverage Days 0 Min 30 Min 60 Min 90 Min 120 Min 180 Min day0 85.33 101.32 110.45 108.75 105.33 101.41 day15 84.01 98.13 108.33 106.29 103.48 98.41

A day30 82.46 99.27 106.37 104.26 102.17 97.25

day0 84.99 98.62 106.62 103.30 100.34 94.30 day15 83.60 98.60 104.32 100.20 97.30 93.55 B

day30 82.19 98.23 104.14 97.66 96.50 92.12 day0 85.18 92.20 96.43 94.45 91.49 84.45 day15 83.63 92.73 95.20 93.36 88.80 83.19 C

day30 82.50 90.26 94.61 92.42 87.27 82.67 day0 85.20 92.02 95.02 92.88 89.77 82.61 day15 83.74 90.51 93.19 88.46 87.32 81.52 D day30 82.15 89.21 92.12 86.84 83.50 79.93

Table 4.33 Interactive effect of diets and time scale intervals on the blood glucose

contents (mg/dl) of volunteers Time scale intervals

Beverage 0 Min 30 Min 60 Min 90 Min 120 Min 180 Min Means

A 83.93 99.57 108.38 106.43 103.66 99.03 100.17a B 83.59 98.48 105.03 100.39 98.05 93.33 96.48b C 83.77 91.73 95.41 93.41 89.19 83.44 89.49c D 83.70 90.58 93.44 89.39 86.86 81.35 87.55d

Means 83.75e 95.09c 100.57a 97.41b 94.44c 89.29d

0 Min. = fasting

Effect of different beverages on the blood glucose level of subjects

60

70

80

90

100

110

120

0 Min 30 Min 60 Min 90 Min 120 Min 180 Min

Time (Minutes)

mg

/dl

Diet A

Diet B

Diet C

Diet D

Figure 4.9 Effect of β-glucan beverage on blood glucose (mg/dl) content of

healthy volunteers Table 4.34 Interactive effect of diets and study duration on the blood glucose

contents (mg/dl) of volunteers

Beverage Study Periods 0 Days 15 Days 30 Days

Means

A 102.10 99.78 98.63 100.17a B 98.03 96.26 95.14 96.48b C 90.70 89.49 88.29 89.49c D 89.58 87.46 85.62 87.55d

Means 95.10a 93.24b 91.92c



when blood glucose level was observed after 15 and 30 days,

respect ively.

The interact ive ef fect of diets (beverages) and study t ime

(Table 4 .32) indicated that the control beverage (0% β -glucan)

possessed the highest blood glucose level of adults when tested

f irst t ime, however, the lowest blood glucose level was observed

in the adult subjects who were fed on diet D (0.6% β -glucan

beverage) when tested after 30 days (Table 4.32) .

The results indicated that level of blood glucose was

significantly affected by the difference in beverages and t ime

intervals. The beverages supplemented with β -glucan showed

pronounced ef fect on the reduction of blood glucose level ,

whereas the control diet did not significantly af fect the level of

blood glucose in the adult subjects . The reduction in blood

glucose level was more when level of β -glucan in the beverage

formulat ions was increased. I t is true due to the assumption that

complex carbohydrates were digested and absorbed more slowly

than simple sugars, resulting in a f lat tened glucose response

curve. The fal lacy was revealed when researchers discovered that

blood glucose and insulin responses varied great ly, independent

of diet c lassif icat ion as simple or complex carbohydrate

(Schauberger e t al . , 1977; Jenkins et a l . , 1983).

The β -glucan has abil i ty to retard the absorption rate of food

in the intest ine due to increased viscosity, thus balancing the

post-prandial glucose and insulin response (Wursch and Sunyer,

1997; Wood et a l . , 2000). The viscous nature of β -glucan physically

slows glucose absorption in the gut . This property is useful in the

formulat ion of products targeting management of diabetes. Wood

et a l . , (1990 and 1994) also reported similar results who prepared

porridge from β–glucan and after consumption demonstrated that

product has reduced postprandial blood glucose level. Jenkins e t

a l . , (2002) showed that a food in which β -glucan is incorporated as

a functional ingredient tends to reduce glycemic indices of that

part icular food addit ion of β -glucan predictably reduces the GI

while maintaining palatabil i ty. Foster-Pwer and Miller (1994) also

observed similar reduction in blood glucose level by the β -glucan

containing food bars. Thus the reduction of blood glucose in the

present study by intake of beverages contain ing β -glucan is in l ine

with the f indings reported above. I t may be concluded from the

present study that diabetic pat ient may use beverages in which β -

glucan is incorporated which wil l help to reduce the level of

blood glucose.

results and discussion 4.1. chemical composition of barley flour

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