With the continuous improvement of people's living standards and the change of consumption concept, higher and higher requirements have been put forward for the product structure, quality, safety and hygiene of food industry, especially for all kinds of traditional and convenient packaged food, which has become a hot spot of consumption in today's food market. But in the process of production, preservation, transportation and sale of these foods, they are easily contaminated and deteriorated, thus losing their commercial value. Although the national food hygiene law has made strict provisions on the hygienic indicators of all kinds of food, it is difficult to meet the standard in general. This not only greatly affects the shelf life of goods, but also is extremely harmful to the protection of people's health.
Although conventional technologies such as high temperature drying, blanching, pasteurization, freezing and preservatives can be used to achieve food insecticidal sterilization and preservation. But most of these equipments are huge, take a long time to process, sterilize incompletely or not easy to realize automatic production, and often affect the original flavor and nutrition of food. Microwave insecticidal sterilization is to make microorganisms in food, such as insects, bacteria, and other microorganisms. At the same time, microwave thermal effect and non-thermal effect are combined to cause the variation of protein and physiological active substances in the body, which leads to the delay and death of microorganisms, so as to achieve the purpose of food insecticide, sterilization and freshness preservation.
Characteristics of microwave sterilization and preservation:
Short time, fast speed. Conventional Industrial Low Temperature Microwave Systems transfer heat from food surface to interior by means of heat conduction, convection or radiation. It often takes a long time to reach the sterilization temperature. Microwave sterilization is the direct interaction between microwave energy and microorganisms such as food and bacteria. Thermal and non-thermal effects work together to achieve rapid heating sterilization. The treatment time is greatly shortened. The sterilization effect of various materials is generally 3-5 minutes.Low-temperature sterilization preserves nutrient composition and traditional flavor. Microwave sterilization is a special thermal and non-thermal sterilization. Compared with conventional thermal sterilization, microwave sterilization can obtain the required sterilization effect at lower temperature and in shorter time. Practice shows that the general sterilization temperature can reach the effect at 75-80 C. In addition, microwave treatment of food can retain more nutrients, color, fragrance, taste, shape and other flavors, and has puffing effect. For example, the vitamin C of vegetable treated by conventional heating is 46-50%, while that of microwave heating is 60-90%, and that of porcine liver heated by conventional heating is 58%, while that of microwave heating is 84%.Energy conservation. Conventional thermal sterilization often results in heat loss in the environment and equipment, while microwave is used to treat food directly, so there is no additional heat loss. In addition, the conversion efficiency from electric energy to microwave energy is 70-80%, compared with 30-50% in general.
Compared with conventional disinfection and sterilization, microwave sterilization equipment does not need boilers, complex pipeline systems, coal yards and transportation vehicles, as long as it has basic water and electricity conditions.Improve the working conditions, save the occupied area. The working environment of the equipment is low in temperature and low in noise, which greatly improves the working conditions. The operator of the whole set of microwave equipment only needs 2-3 persons. It is widely used in agaric, ginseng, flowers, onion, ginger and garlic slices. The heating, drying and sterilization of jujube slices, chili peppers, dehydrated vegetables, soybean products and other products, through microwave sterilization and preservation technology, not only won't destroy the original nutritional components of materials, but also the hygienic indicators can be completely lower than the national food hygienic standards, which can fully meet the export-grade standards of food, and greatly prolong the shelf life of food.
See the news list>>