Question

What are different methods of preserving food? 

Answer 1

Pasteurization: -

i) This method is used to preserve milk and is discovered by Louis Pasteur.

ii) In this process milk is heated to 71 C and then cooled rapidly.

iii) The bacteria become retorted in growth.

iv) Hence the milk is preserved for few days.

Refrigeration: -

i) In this process food is kept below freezing point.

ii) This retorted the growth of enzymes and bacteria.

iii) Quick freezing helps in to maintain the taste of food.

iv) By this process meat, fruit and vegetables are preserved.

Dehydration: -

i) In this process water from food is removed.

ii) Dry food can remain safe for a long time because bacteria cannot grow on

it without water.

iii) Meat and some vegetables are preserved by this method.

Canning: -

i) In this method food is first heated at very high temperature to kill

bacteria.

ii) Then food is sealed in metallic container.

iii) Hence food is safe from contamination.