Preservation by Dehydration

Dehydration, in food processing, ensures that by removing water, most types of food can be stored for infinite periods, thereby inhibiting the growth of microorganisms. Dehydration is one of the oldest food preservation methods and has been used in sun-drying seeds by prehistoric peoples. Sun-drying slices preserved food from the North American Indians, dried eggs from the Chinese, and dried fish and rice from the Japanese.

Dehydration equipment for various food items varies in shape and includes tunnel driers, kiln driers, cabinet driers, vacuum driers, and other types. Now available are lightweight devices suitable for home use. A basic design objective is to shorten drying time, which helps to maintain the food product's basic character. Vacuum drying is particularly beneficial for fruits and vegetables. Freeze-drying benefits heat-sensitive products through dehydration without intermediate thaw in the frozen state. Freezing meat provides a material of excellent consistency that closely resembles fresh meat when re-hydrated.