Generally speaking, in the process of milk processing, because of the production conditions and processing technology, microorganisms exceed the standard, we need to do a good job of sterilization and disinfection in order to meet the requirements of consumption.
Microwave is the best sterilization and preservation technology. Microwave milk sterilization equipment treatment of milk safety and hygiene, high nutritional value, received a warm welcome from the majority of consumers.
Characteristics of microwave milk sterilization equipment:
- After microwave sterilization, the color, smell, taste and tissue state of cow milk will not change.The domestic and foreign studies show that the microwave treatment is compared with many traditional processing methods, and the nutrient elements can have a large retention.
- The bacteriostatic effect of microwave will make milk have a shelf life of more than one year at room temperature.
- The cost of microwave sterilization cow milk equipment is far less than that of traditional UHT+sterile cold filling.
- Microwave milk sterilization production line can be seamlessly connected with filling production line, which is convenient to use.
- Microwave sterilization is the same as microwave heating and microwave drying, microwave can transmit into the material, so microwave sterilization is completed as a whole, and has the characteristics of simultaneous.A. The simultaneous sterilization and disinfection of each part of the material: that is, the surface and interior of the material can be sterilized at the same time.B. The simultaneous sterilization time can ensure that the material sterilization process is the same.
- Milk was sterilized and sterilized by microwave sterilization equipment. After fresh milk was treated at 82 ℃ for a few seconds, miscellaneous bacteria and Escherichia coli could completely meet the hygienic requirements. The rate of sterilization is very fast.
Mechanism of Microwave Sterilization Mechanism of Milk:
Microwave sterilization function is an extension of microwave heating, which is mainly characterized by changes in cell physiological activity of bacteria after interaction between microwaves and bacteria and their cells.
Thermal effect: microwave energy is absorbed together in the food watch, and the temperature rises. The structure of microbial protein changes and then loses its biological activity. Cause the bacteria to die or suffer serious interference to prevent reproduction.
The non-thermal effect: a large amount of electrons, ions and other charged particles generated by the microorganism are changed in a combination state and a movement rule. In addition, the microwave can also cause the bacterial cell gene to be mutated, thereby seriously damaging the normal reproduction of the cell.
Application scope of microwave sterilization equipment:
Microwave sterilization is now widely used in liquid foods, such as dairy products, vegetable and fruit juice drinks, beer, seasoning, and the like. The liquid is easy to be mildewed and the bacterial content exceeds the standard, and the microwave sterilization can kill various bacteria in the beverage, and can prevent the mildew in the storage process. Using microwave sterilizer to sterilize rice wine, soy sauce and other liquids, not only the bactericidal effect is good, but also the cost is lower than that of conventional sterilization. After microwave sterilization of beer, the total colony count of beer was less than 14 / ml, coliform group, which was in accordance with the national standard gb4927-85.
Comparison of the sterilization process:
Pasteurization produces a thermal force field that allows the proteins that make up bacteria to solidify and end their lives in the event of heat. Pasteurized environment is a physical property. Different sterilization and disinfection temperatures reflect that bacteria are killed in temperature fields with different degrees of heat.
After pasteurized, there are still a small number of bacteria or bacterial spores resistant to high temperature, so pasteurized milk should be stored at about 4 ℃ for a maximum of 16 days.
Water bath heating sterilization is a direct injection of steam, which heats up the water of the hot water tank to a predetermined temperature, and then injects the process water into the process tank. At the same time, the process water in the pot is constantly recycled and sterilized by circulating heating and sterilization through the water vapor mixer.
- The water bath heating and sterilizing equipment is heavy and bulky, and occupies a large area.
- a large amount of water resources are consumed, the conversion rate of the electric energy to the heat energy is low, and the energy utilization rate is low.
- In the process of high-temperature sterilization, the nutrient components in the milk are more and more destructive.
- If the milk is to be heated after packaging, it is difficult to operate, and it is necessary to put the milk in order by means of special tools.
- Cross-contamination can be easily caused by the cooling process of flowing water and ice water.
Compared with traditional food sterilization technology, microwave sterilization technology has long shown considerable advantages and is more widely used. With the deepening of scientific research, the application of microwave technology, such as microwave sterilization technology, microwave drying technology and so on, in the food industry will become more and more common, which will bring inestimable new opportunities for the development of food enterprises in the future.