What's the difference between tetra pak brick and Kangmei bagged milk?

Different sterilization methods have different shelf life.

Pasteurization is widely used for milk packaged in glass bottles, plastic bags and roof cartons. Fresh milk contains various bioactive substances (some people call them "vital elements"). Although the content is small, it is very afraid of heat. Scientist Pasteur proved through a large number of scientific experiments that if the processing temperature exceeds 85℃, the nutrients in milk will be destroyed a lot. Therefore, people call the disinfection method of milk below 85℃ pasteurization, and regard it as the most scientific processing technology of milk. The nutritional value of fresh milk produced by pasteurization is basically the same as raw milk. But the shelf life is usually only two or three days.

Another kind of packaging is the so-called "tetra pak" and "Combibloc", that is, UHT-ultra-high temperature instant sterilization technology. It is made by heating milk to above 130~ 150 degrees Celsius for only a few seconds, then rapidly cooling to normal temperature, and then filling and sealing with paper, aluminum and plastic composite sterile materials under sealed aseptic conditions. The application of UHT technology in dairy industry began in the late 1940s. 196 1 year, Tetra Pak Company of Sweden developed an aseptic packaging system to package UHT sterilized products in the same aseptic container in a continuous and closed aseptic environment. UHT packaged milk can be stored for a long time at room temperature, and the comprehensive cost is low. The technology monopoly is in the hands of a few enterprises such as Tetra Pak, and the cost of simple packaging is higher. Bailey bag is a plastic package made of black and white composite film, which has low cost and reduces the price cost of dairy products. The shelf life is one month.

However, they are all filled after ultra-high temperature sterilization at 130 ~ 150℃. The whole process is completed in a few seconds, and the temperature can reach 140℃, which can not only kill harmful bacteria. It can also preserve nutrition to the maximum extent. But compared with pasteurization, it still loses nutritional quality.