Use of High Temperatures for Food Preservation

Use of High Temperatures for Food Preservation
Preservation of food by the use of heat finds very wide applications compared to other methods.

Heat may be used either for processing or conversion of foods or simply as a means or preserving the food.

In heat processing or conversion the application of heat is used primarily to effect chemical changes in food.

Cooking, frying and baking involve both processing and preservation operations.

Cooking makes food palatable and tender and also destroys a large proportion of microorganisms and natural enzymes.

Cooked foods can be stored for several days provided they are protected from recontamination.

Refrigeration cooked food is a normal household practice to prolong the storage time.

However, cooking will not sterilize a product.

Cooking also destroys the toxin formed by Clostridium botulinum during a ten minute exposure of the food to moist heat at 100 degree C.

Thus cooking provides a final measure of protection for consumer form food borne diseases.

The killing of microorganisms by heat is due to thermal denaturation of protein and enzymes of the microorganism required for its metabolic activity and growth.

The heat treatment necessary to kill the organisms or spores varies with the kind of organism, its state and the environment during heating.

The type of heat treatment will depend on the kind of organism to be killed, other preservative methods to be employed and the effect of heat on the food.

The use of heat also affects the food adversely and hence it is necessary to use only mild heat treatment that ensures freedom from pathogens and enzyme activity and enhance the self life of the food.
Use of High Temperatures for Food Preservation