ABSTRACT
Many of the conventional food preservation methods used at present and discussed here have several disadvantages. High-heat treatment given to foods for safety and long shelf life results in loss of heat-sensitive nutrients (e.g., thiamine, riboflavin, folic acid, and vitamin C); denatures proteins and causes changes in texture, color, and flavor; and induces formation of new compounds through covalent bonds (e.g., lysinoalanine). Low-heat processing, such as pasteurization, minimizes the disadvantages of high-heat processing of foods, but the foods have limited shelf life even with refrigerated storage. Drying and freezing also reduce nutritional and acceptance qualities of food, especially when stored for a long time, and moreover, not all food can be stored by drying or freezing. Irradiated foods have not been well accepted by consumers. Many of the chemical preservatives used are of nonfood origin and have limited efficiency.
