STD-5, CHAPTER-6: SPOILAGE AND WASTAGE OF FOOD AND FOOD PRESERVATION, EXERCISE QUESTION AND ANSWERS

 

A.     FILL IN THE BLANKS.

1.      Micro-organisms like bacteria and ________ spoil the food.

Ans: Fungi

2.      Insects make their home in _______ and _______ places.

Ans: moist and dark places

3.       Enzymes can be harmful because they can cause ______ of fruits and vegetables.

Ans: spoilage

4.       Snacks, like biscuits and chips, should be stored in _______ jars.

Ans: airtight

5.      The growth of micro-organisms slows down at _______ temperatures.

Ans: lower

B.      WRITE TRUE OR FALSE FOR THE FOLLOWING STATEMENTS.

 

1.      Growth of bread moulds, on bread, indicates that it has got spoiled.                    True

2.      Vinegar is used as a preservative.                                                                                   True

3.      It is safe to drink unpastuerised milk.                                                                            False

4.      We can eat more than the required quantity.                                                              False

5.      We may eat spoiled food rather than wasting it.                                                         False

 

C.      TICK THE CORRECT OPTION.

 

1.      A natural insect repellent, found in our kitchens, is -

(a)   salt                (b) sugar         (c) turmeric powder           (d) wheat flour

      Ans: turmeric powder

2.      Dry foods, like cereals and nuts, are preserved by -

(a)   Adding salt and sugar         (b) vacuum packing          (c) dehydration         (d) pasteurisation

      Ans: vacuum packing

3.      Fruits and vegetables get ripened due to the action of-

(a)   enzymes       (b) bacteria        (c) fungi       (d) insects

       Ans: enzymes

4.      The least perishable food item, from the following, is-

(a)   milk                      (b) biscuits

(c)    meat                    (d) curd

      Ans: curd

5.      The chances of spoilage of food can be reduced by keeping the food -  

(a)   moist       (b) warm        (c) at low temperatures       (d) in open containers

       Ans: at low temperatures

D.     ANSWER THE FOLLOWING QUESTIONS IN BRIEF.

 

1.      State two factors that contribute to the fast growth of micro-organisms.

Ans: Two factors that contribute to the fast growth of micro-organisms are, moisture and temperature.

2.      What is likely to happen to curd if it is not stored in the refrigerator?

Ans: If curd is not stored in the refrigerator, then it is likely to change its smell and will become sour. In other words, it will get spoiled.

3.      What do you understand by food preservation?

Ans: Food preservation is the process of treating and handling of food to stop, or slow down, the spoilage caused by micro-organisms.

4.      How can we protect our food from insects, worms and rats?

Ans: i) We should keep the cupboards, shelves and containers clean and dry.

ii) This will prevent them from making a home at places where our food items are kept.

5.      Why does food stay fresh for a longer time when stored in a refrigerator?

Ans: i) The temperature is low inside a refrigerator.

ii) Micro-organisms and enzymes get deactivated at low temperatures and hence, the spoilage of food gets prevented.

E.      ANSWER THE FOLLOWING QUESTIONS.

 

1.      Give any three reasons for spoilage of food.

Ans: Three reasons for spoilage of food are, micro-organisms, enzymes, insects, worms and rats.

2.      How is food preservation useful to us?

Ans: Food preservation is helpful in many ways:

i)                    It helps to maintain nutritive value of food.

ii)                  It increases the shelf life of food, thus, increasing its supply. Many perishable foods can be preserved for a long time.

iii)                It makes seasonal foods available throughout the year.

3.      Why is it important to check the manufacturing and the expiry date of packaged food items before consuming them?

Ans: Some food items are preserved by the process of canning, bottling or by vacuum packing. But, these food items start to spoil after a certain period of time. So, it is important to check the manufacturing and the expiry date of packaged food items before consuming them.

4.      Explain the following methods of food preservation:

(a)   Dehydration  (b) Canning and Bottling    (c) Pasteurisation

Ans: a) Dehydration: The process of food preservation in which water content of the food stuff is removed, is called dehydration.

b) Canning and Bottling: Food is cooked and sealed in sterile cans or jars and these containers are boiled to kill any remaining bacteria.

c) Pasteurisation: In this process, food product is subjected to pressurised heating, for a short time, followed by immediate cooling.

5.      Rakesh bought two raw papayas. He kept one papaya in the refrigerator and other papaya on the kitchen shell. Which will ripen and Why?

Ans: The papaya kept in the kitchen shell will ripen faster, due to the action of enzymes. Whereas, the action of enzymes slows down for the papaya, which is kept at a low temperature inside the refrigerator.