Tag: methods of preserving food

Questions Related to methods of preserving food

Food is preserved at low temperature because 

evs - i methods of preserving food food spoilage and food preservation food poisoning and food preservation methods food spoilage, adulteration and preservation

  1. Bacterial attack is minimised

  2. For easy cooking

  3. For easy digestion

  4. All the above

Show answer
Correct Option: A
Explanation:

Food products like fruits and vegetables are kept at low temperature to maintain its freshness, longevity and taste. Respiration uses stored starch and enhances ageing process. Low temperature minimizes the bacterial attack on food and also decreases respiration rate.

Thus, the correct answer is option A.

Which among the following is the most reason for storing green coloured apples at low temperatures?

evs - i methods of preserving food food spoilage and food preservation food poisoning and food preservation methods food spoilage, adulteration and preservation

  1. The rates of respiration and photosynthesis are reduced

  2. The rate of respiration is reduced

  3. The rate of photosynthesis is reduced

  4. Respiration and photosynthesis are completely inhibited

Show answer
Correct Option: B
Explanation:

When green coloured apple are stored in low temperature the cellular proccess in the apples also gets reduced for conserving energy due to which the rate of respiration is reduced and the aging process is slowed down.

So, the correct answer is 'The rate of respiration is reduced'

Which of the following are correct?
(i) In canning, heating of food products is not required
(ii) Bacteria and fungi can't be active in absence of moisture.
(iii) Meat and fish are covered with dry salt to check the growth of bacteria.
(iv) At high-temperature fruits, eggs and meat can be stored for a long time.
(v) Use of oil and vinegar prevents spoilage of pickles.

evs - i methods of preserving food food spoilage and food preservation food poisoning and food preservation methods food spoilage, adulteration and preservation

  1. (i), (ii), (iii)

  2. (ii), (iii), (v)

  3. (iii), (iv), (v)

  4. (ii), (iii), (iv)

Show answer
Correct Option: B
Explanation:

i) Canned foods are boiled in the can to kill all the bacteria and seal the can to prevent any new bacteria from getting in.

ii)  Bacteria and fungi in the absence of moisture cannot grow rapidly as in the presence of moisture.
iii) The salt is a water absorbent. Hence, it removes water from any food as a result in the absence of water bacteria don't multiply and hence it acts as a preservative.
iv) Fruits, eggs, and meat can be stored for a long time at a very low temperature to avoid spoilage from microbes.
v) Use of oil and vinegar prevents spoilage of pickles because bacteria cannot live in such an environment. 
  • The correct answer is OPTION B.

Acetic acid looks like ice due to freezing at ______ $^oC$.

evs - i methods of preserving food food spoilage and food preservation food poisoning and food preservation methods food spoilage, adulteration and preservation

  1. 0

  2. -10

  3. 17

  4. 4

Show answer
Correct Option: A

Why the food can be kept for a longer time in cold house than in normal conditions?

evs - i methods of preserving food food spoilage and food preservation food poisoning and food preservation methods food spoilage, adulteration and preservation

  1. Insect can not enter

  2. Bacterial multiplication stops

  3. Bacterial multiplication is reduced

  4. There is plasmolysis at low temperature

Show answer
Correct Option: A

The temperature in your freezer should be

evs - i methods of preserving food food spoilage and food preservation food poisoning and food preservation methods food spoilage, adulteration and preservation

  1. -2$^o$C

  2. -9$^o$C

  3. -12$^o$C

  4. -18$^o$C

Show answer
Correct Option: D
Explanation:

the correct answer is '-18ooC'

The freezer temperature is maintained at 0F or -18 degrees celsius as it is the ideal temperature to freeze food stuff.
o 

The temperature inside your fridge should be

evs - i methods of preserving food food spoilage and food preservation food poisoning and food preservation methods food spoilage, adulteration and preservation

  1. $10^oc$

  2. $4^oc$

  3. $0^oc$

  4. $-2^oc$

Show answer
Correct Option: B
Explanation:
  • The temperature range between 1 to 4 degrees Celsius is an ideal balance between the temperature required to stop/avoid microbial growth and not freeze the food that is to be preserved. 
  • At 0 or -2 degrees Celsius the microbial growth is stopped but the food gets frozen whereas 10 degrees Celsius won't stop microbial growth. 
    Hence, correct option is B.

Pasteurization is heating at

evs - i methods of preserving food food spoilage and food preservation food poisoning and food preservation methods food spoilage, adulteration and preservation

  1. $120^{0}$C for 60 minutes

  2. 60-$70^{0}$C for 30 minutes

  3. $70^{0}$'C for 60 minutes

  4. $80^{0}$C for 30 minutes

Show answer
Correct Option: B
Explanation:

In the classic pasteurization treatment of milk, the milk was exposed to a temperature of about $63^{0}$C for 30 minutes. Most milk pasteurization today uses higher temperatures, at least $72^{0}$C, but for only 15 seconds. 


We can keep food for longer duration in cold storage than in ordinary cupboard because

evs - i methods of preserving food food spoilage and food preservation food poisoning and food preservation methods food spoilage, adulteration and preservation

  1. Insects cannot cause infection

  2. Bacterial multiplication is completely prevented

  3. Bacterial multiplication is greatly reduced

  4. Low temperature causes plasmolysis

Show answer
Correct Option: C
Explanation:

We can keep food for longer duration in cold storage than in ordinary cupboard because bacterial multiplication is greatly reduced. At room temperature, bacteria grow rapidly. When food is stored at cold temperature, bacteria enters a dormant stage. Also, water content of the food freezes in cold storage. This prevents bacteria from multiplying and food spoiling.

Thus, the correct answer is 'Bacterial multiplication is greatly reduced.'

Food can be kept unspoiled at

evs - i methods of preserving food food spoilage and food preservation food poisoning and food preservation methods food spoilage, adulteration and preservation

  1. High temperature

  2. Low temperature

  3. Osmotic temperature

  4. All the above

Show answer
Correct Option: B
Explanation:

Food can be kept for longer duration and unspoiled at low temperature than in ordinary temperature because bacterial multiplication is greatly reduced. At room temperature, bacteria grow rapidly. When food is stored at cold temperature, bacteria enter a dormant stage. Also, the water content of the food freezes in cold storage. This prevents bacteria from multiplying and food spoiling.

Thus, the correct answer is 'Low temperature.'