Milk refers to fresh milk and all products made of milk as the main raw material, including raw milk, pasteurized milk, ultra-high temperature sterilized milk, yogurt, milk powder, condensed milk, butter, ice cream, ice cream, cheese and other products.
The fresh milk people drink mainly comes from cows, buffaloes and sheep, as well as horses. According to the traditional production mode, after milk is extruded, it is transported from the pasture to the processing plant through several links: that is, the small tank of the milk producer is poured into the large tank (barrel) of the purchaser, and then transported to the stainless steel refrigerated tank of the milk processing plant, and the milk is cooled to below 10℃ in about one hour.
This decentralized collection method is prone to quality problems. If you pour a can of spoiled milk into a big can, it will affect the quality of the whole can of milk. Therefore, it is very important to strengthen quality inspection and thoroughly clean and disinfect large and small tanks and barrels in time. The deterioration of fresh milk is mostly caused by bacterial reproduction.
It may also deteriorate due to protein decomposition or fat oxidation. Raw milk already contains a lot of bacteria. According to statistics, milk of dairy cows contains more than 500 bacteria per milligram. When the number of bacteria per milliliter of milk increases to 107, milk will be obviously spoiled. Therefore, the key to control the quality of fresh milk lies in timely cooling and sterilization, strengthening the disinfection of containers and preventing secondary pollution.
Fresh milk is a good culture medium for microorganisms, in which the moisture content is high, the pH value is close to neutral, the fat, protein and lactose content are high, and the nutritional value is rich.