MODULE 17 FOOD TECHNOLOGY AND PRODUCTION

17.1 The methods and substances used in food technology

1. The purpose of processing food – killing microorganisms- facilitate food digestion- make food last longer

2. Chemicals used in food processing

Chemical FunctionPresevative Prevents food form spoiling in a short timeArtifical colouring Improves the appearance of foodBleach Removes undesired colourFlavouring Enhances flavourSweetener Gives sweet tasteStabilizer Decreases the separation rate in emulsionEmulsifier Breaks oil droplets into small droplets Antioxidant Prevents oxidation of food

3. Technology used in food processing and packaging

Technology Explanation Disadvantages Advantages

Canning Food is cooked, sterilized and saved in can

- destroys almost all the nutrients- changes the natural taste of food

-Destroys all the microorganisms present in the food- food can last longer

Pasteurization Food such as milk is heated at 63 0C for 30 minutes or 72 0C for 15 second

-The spores of bacteria cannot be destroyed - must be refrigerated, can last for several days only

- most of the nutrients and the natural flavour and maintained

Dehydration Water the food is removed. There are three types:- place food under sunlight- hot air is passed through the food- food in dehydrated under vacuum

- Most nutrients are destroyed

- not all bacteria and spores are destroyed

- the natural flavour of the food is maintained- food can be kept longer

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Freezing Food is kept at a temperature of less than – 18 oC

- frost formed in the food destroys nutrients and flavour of the food- bacteria and spores are not killed, only growth of bacteria is stopped

- maintain the freshness of the food - best method for keeping of food such as meat and seafood fresh

Cooling Food is kept at a temperarure between 0oC and 5oC

- bacteria and spores are not killed, only growth of bacteria is stopped

- Nutrients and flavour of the food are maintained

Vaccum packaging

- food are kept in a vaccum to prevent aerobic bacteria from spoiling the food

- this method is limited to certain foods only- bacteria and spores are not killed

- Nutrients and flavour of the food are maintained

Irradiation Food is irradiated with radioactive rays such as the gamma rays

- nutrients in the may be destroyed

- all the microorganisms are killed

17.2 Ways to improve food productionWays to increase the quality and quantity of food :(a) Use of quality breeds(b) Use of modern technology(c) Provide guide and education for farmers(d) Carry out research and development(e) Efficient land management(f) Optimise the use of land irrigated areas

17.3 Practicing critical and analytical thinking when selecting processed food

1. The Food Act 1983 and The Food Regulations 1985 protect the user’s rights and health from harmful processed food in the market.

2. All processed food packaging labels must contain the following information :

a) Type of foodb) The ingredientsc) Net weightd) Expiry datee) Name and address of the manufacturer

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Activity 1

Activity 2

Activity 3

Figure 1

a) Name the technology used for the above processed food.

P : _____________________________

Q : _____________________________

R : _____________________________

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The purpose of processing food

i) ii) iii)

Chemicals used in food processing and their function

viii)

vii)

vi)

i)ii)

iii)

iv)

v)

b) State one advantage and one disadvantage for each process.

Advantage DisadvantageP

Q

R

Assessment

Objective question

1. Which of the following is not a reason for processing food ?

A to increase the productivity of foodB to kill microbes in foodC to preserve food to last longerD to retain as much nutrients as possible in food

2. How do preservatives make food last longer ?

A Its prevents the dehydration of foodB Its prevents the growth of microorganismC Its makes emulsification easierD It makes food more attractive

3. Which method of food processing does not destroy the vitamins in food ?

A vacuum packaging C DehydrationB freeze drying D irradiation

4. Which food is usually dehydrated before packaging in a factory ?

A Milk powder C tomatoesB green vegetables D meat

5. Which method of preserving food uses radioactive substances ?

A irradiation C vacuum packagingB pasteurization D Dehydration

6. What will improve the quality and quantity of food production?

A pesticides C education and guidance for consumersB synthetic hormones D optimum use of land for agriculture

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7. Which practice are examples of an integrated cultivation system?

I breeding livestock on oil palm plantations II breeding small fishes in paddy fieldIII planting many types of crops on the small area

A I and II C II and IIIB I and III D I, II and III

8. Which efforts ensure the optimum use of land for food production?

I developing marshes for fish breedingII developing abandoned mining sites for crop cultivationIII opening up more forest land for agriculture

A I and II C I and IIIB I and III D I, II and III

9. Information that must be stated on a food label include

A the name and type of free gift obtained for purchaseB the unit price of foodC the calorie content of the foodD the date of manufacture and date of expiry

10. What are the rights of consumers?

I the right to choose III the right to taste foodII the right to obtain

A I and II C II and IIIB I and III D I, II and III

STUCTURED QUESTION

1. Figure 1 show the label on a tin of Ladybird Margarine

Figure 1

a) State two other information required to be shown on a label according to Food act.

(i) _______________________________________________________

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(ii) _______________________________________________________[2 marks]

b) What should a consumer do if the information on a food label is incomplete?

_______________________________________________________________[1 mark]

c) What is the function of the antioxidant contained in a margarine ?

_____________________________________________________[1 mark]

d) Is Ladybird Margarine suitable for a heart patient?Give a reason for your answer.

________________________________________________________________[1 mark]

2. Figure 2 shows the advantages of using quality breeds.

Figure 2

a) Name the process of getting the Tenera species of oil palm

__________________________________________________[1 mark]

b) Name two good qualities of the Tenera species.

(i) ________________________________________________

(ii) ________________________________________________[2 marks]

c) Besides using quality breeds in a oil palm plantation, name two other activities that can be carried out in the plantation to increase efficient use of land.

(i) _______________________________________________________

(ii) _______________________________________________________[2 mark]

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d) How does using modern technology in an oil palm plantation help in increasing the quality and quantity of food production?

________________________________________________________________

________________________________________________________________[1 mark]

Essay question

1.a) Chemicals know as food additives are usually added to food during food processing. State four types of common used food additives. Explain the function and give one example for each of the food additive

[4 marks]

b) Figure 3 shows four different types of food

Study the type of food carefully. Explain how you built a concept based on the figure above. Your explanation should include the following:

(i) Identify two common features [2 marks](ii) Build an initial concept [1 mark](iii) Give other examples and non examples [2 marks](iv) Explain the actual concept [1 mark]

Answer

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Type of food

Frozen meat Pasteurized milk

Powdered milk Canned sardine

Activity 1i) killing microorganisms ii) facilitate food digestioniii) Make food last longer

Activity 2i) colouring ii) bleach iii) sweetener

iv) stabilizer v) flavouring vi) emulsifier

vii) antioxidant viii) Preservative

Activity 3a) P : vacuum packing Q : dehydration R : canning

c) advantages :P ; does not spoil the taste and the nutrients in the foodQ : Prevents the growth and reproduction of microorganismsR : kill all microorganisms

Disadvantages :P : anaerobic bacteria can continue livingQ : bacteria and spores are not destroyedR : the taste of food changes and all the vitamins are destroyed

Objective question

1.A 2.B 3.A 4.D 5.A 6.D 7.A 8.C 9.A 10.D

Structure question

1. a) (i) quantity (ii) an expiry date

b) Make a report to a consumer’s association

c) to prevent or slow down the oxidation of food exposed to air

d) Yes, It is cholesterol-free

2. a) selective breeding

b) (i) thick mesocarp (ii) large kernel

c) (i) planting cover crops to increase income and to prevent soil erosion (ii) rearing cows in the plantation to increase in come and help in controlling the vegetable under oil palm trees

d) Help to speed up the collectionof oil palm fruit

Essay question

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1. (a) Preservative- To prevent growth ofmicroorganisms in the food - Example: Sulphur dioxide

Bleach-To make the food lookwhite and clean- Example: Benzoil peroxide

AntioxidantTo slow down the rate of oxidation of fats in food and prevent them from turning rancidExamples: Ascorbic acid Emulsifier

- To prevent the fat and water(in thefood) from separating into two layers- Example: Lecithin

(b) (i) Common features: They all are processed food They all last longer than fresh food

(ii) Initial concept: Processed food can last longer than fresh food

(iii) Example:Vacuum packaging peanut

Non-example:Fresh mushrooms

(iv) Actual concept: In order to make food last longer and prevent wastage of food, fresh food is processed using modern technology

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