NUTRITION AND FOOD TECHNOLOGY
For thousands of years, man has been making efforts to grow more food for storage so that it can be used when needed. Modern man knows how to preserve food for use subsequently when needed.
Man has adopted modern techniques of food preservation in which its nutritional value and taste are preserved. Foods are damaged by bacteria; fungi and other micro-organisms, which occur everywhere. These organisms make food unsafe for use and storage, so it is necessary to kill bacteria or other organisms as soon as they enter food.
Early methods of preservation affected the taste of the preserved food, but modern scientific techniques prevent contamination of food, keep the taste and make it consumable even after a long period of storage. To achieve this, temperature plays an important role.
Food that we take is usually made up of dead tissue and it can be spoiled for two reasons, either the food is contaminated and destroyed by bacteria or fungi or the enzymes still active in tissue start breaking down the cells, thus making food poisonous and tasteless to eat.
All bacteria, fungi and micro-organisms must be killed or their growth must be retarded in order to protect the food from spoilage. Heat is the best source, as extreme increase in temperature retards bacterial growth and enzymes can also be denatured. Thus temperature extreme can be useful in the preservation of food.