(i) Food preservation adds variety to the food. For example, in the absence of fresh peas during the hot summer months, canned or dehydrated peas may be made use of.
(ii) Food preservation increases the shelf life of food. Pineapples, cherries and other fruits and vegetables may be preserved by different methods for long periods of time.
(iii) Food preservation increases the food supply.
(iv) Food preservation decreases the wastage of food. Excess foods which would have otherwise been wasted, when processed and preserved add to the existing supplies, thus also decreasing the wastage of food.
(v) Food preservation decreases dietary inadequacies. Variety in diet is brought about with the help of preserved foods. For example, some Middle-East countries do not grow any vegetables due to arid soil conditions, This shortcoming is overcome through the import of fresh and preserved fruits and vegetables.
However, the Middle East countries are the chief exporters of dates and dry fruits. Likewise, certain regions of a country which may be lacking in a particular food item, can make good the deficiency by procuring them from various regions where it is plentiful. In the snow-bound areas of the Himalayas most often, food is brought in from other parts of the country.