The use of low-temperature refrigerated foods can inhibit the growth of microorganisms, preserve the flavor and nutrients of foods, and the original nature and freshness of foods. Low temperature refrigeration, also known as food cold processing, includes four processes of cooling, freezing, freezing, and thawing. The temperature at which the general food is cooled is ±4°C to 0°C. Freezing refers to freezing the moisture contained in the food into ice, usually at -8 °C. It is then preserved in the case of ice.


Freeze-drying is a drying method in which the raw material is removed from the frozen ice crystals directly into water vapor under vacuum conditions. It can effectively prevent the oxidation and deterioration of heat sensitive substances, prevent the surface of the product from hardening, enhance the rehydration, and maximize the original quality of the food. This technology is now widely used in the production of frozen foods.


Vacuum freeze-drying technology, referred to as freeze-drying technology, is the world's best food processing technology, which can retain the color, fragrance, taste, shape and nutrients of the product to the utmost extent. After packaging, it can be degraded at room temperature for five years. After rehydration, it looks like fresh. This technical device can process any food and medicine. After sublimation, it becomes a freeze-dried food.