At present, there are two main methods of pasteurization in general use:
First, the milk is heated to 62~65℃, maintain 30 minutes. Using this method, can kill all kinds of growth pathogenic bacteria in milk, sterilization efficiency can reach 97, 3%~99, 9%, after disinfection residual only part of the thermophilic bacteria and heat-resistant bacteria and spores, but most of these bacteria are lactic acid bacteria, lactic acid bacteria is not only harmless to people but beneficial to health.
The second method is to heat the milk to 75~90℃ and hold the milk for 15~16 seconds. The sterilization time is shorter and the working efficiency is higher. However, the basic principle of sterilization is that the pathogenic bacteria can be killed, but the temperature is too high will have more nutritional loss.