USA: Hydrostatics high-pressure disinfection method
Michael C. Qian and colleagues from Oregon State University in the United States pointed out that UHT sterilization can produce milk that can be kept fresh at room temperature for up to 6 months, but it can produce a steaming taste, which is the main reason why it is not popular in the United States. In the paper published in the early bi weekly Journal of Agricultural and Food Chemistry, they introduced a method called Hydrostatics high-pressure processing (HPP), which means that milk is sterilized under high pressure to keep it fresh without any cooking smell. Milk is treated at a pressure of approximately 85000 pounds per inch for 5 minutes, and the disinfection temperature is lower than that of commercial pasteurization, which can reduce the generation of compounds related to cooking taste. HPP milk can be stored for at least 45 days under refrigeration conditions. France: Degreasing and heating preservation method
It is reported that this new method involves first skimming fresh milk, allowing the skimmed milk to pass through a pore size of 0.5 μ M's special film filters out the microorganisms inside, and then heats the skimmed milk at 96 ℃ for 6 seconds. The purpose of heating is not to sterilize or disinfect, but to inactivate the enzymes in the milk and avoid spoilage during storage. Usually, the processing of ultra-high temperature milk involves heating fresh milk at 120-140 ℃ for 2 to 4 seconds, while the process of disinfecting fresh milk involves heating the milk to around 60-90 ℃ before rapidly cooling down. The new preservation method is different from both of the above. It is said that raw milk processed using new techniques can be kept fresh for 4 to 6 months at room temperature, and some consumers in European countries believe that its taste is the same as disinfected fresh milk after tasting it. However, this new process is currently only applicable to skimmed milk, as the sterilization treatment of fat in milk still requires traditional ultra-high temperature processes.
In addition to the above fresh-keeping methods, the fresh-keeping of Yanchang dairy products can also be achieved through Chlorine dioxide fresh-keeping method, ultrasonic fresh-keeping technology, ultraviolet fresh-keeping technology, irradiation fresh-keeping technology, ultra-high pressure fresh-keeping technology, etc.
The continuous development of various disinfection technologies has made it possible to continuously extend the shelf life of dairy products. However, turning this possibility into reality requires the support of relevant equipment. At present, the common milk preservation equipment in the market mainly includes high-temperature disinfection equipment and low-temperature refrigeration equipment.
High temperature disinfection equipment
Due to the inability of low-temperature sterilization to kill all microorganisms, especially spores, low-temperature storage is required, but the shelf life is only 3 months. In order to extend the shelf life, milk can be sterilized under high temperature and pressure. In this way, the shelf life of dairy products can be appropriately extended. It is understood that common high-temperature disinfection equipment nowadays includes: vertical high-pressure sterilization pot, horizontal high-pressure sterilization pot, rotary sterilization equipment, air conditioning sterilization pot, and so on.
Low temperature refrigeration equipment
Food refrigeration technology is a science that utilizes artificial refrigeration technology to reduce food temperature and achieve long-term storage and processing of food. As early as more than 3000 years ago, the working people in our country have used natural ice to preserve food, which can be said to have a long history of refrigeration in our country. With the development of the times and technological progress, people can use mechanical refrigeration to preserve and process food, and on this basis, a complete food refrigeration chain system has been formed.
We know that there are two types of milk on the market today: low-temperature milk and room temperature milk. The shelf life of low-temperature milk is directly related to whether it is refrigerated. Therefore, the application and popularization of low-temperature refrigeration equipment play a significant role in improving the safety of dairy products. The frequent dairy product safety incidents make us realize the seriousness of domestic food safety problems, and at the same time let more people see that there are obvious deficiencies in China's dairy product processing equipment industry at present. Whether it is sterilization equipment enterprises or production and processing equipment, packaging and testing equipment enterprises, they need to improve their food safety awareness, and contribute to China Foods Limited's food safety through continuous equipment output.
