Yogurt is made from fresh milk or skim milk. When pure cultured lactic acid bacteria are added to the sterilized milk for fermentation, lactose in the milk is decomposed into lactic acid. When the PH value reaches a certain level, casein begins to precipitate and coagulate into yogurt. Yogurt is delicious and nutritious, and protein in milk becomes easier to digest and absorb. Lactic acid bacteria can also synthesize vitamin C, vitamin B and folic acid in human intestine. Home-made yogurt is completely feasible, and delicious yogurt can be made by using fresh milk or milk powder. Here's how to make delicious yogurt with fresh milk:

1. Preparation. Strains for yogurt (pure yogurt sold in the market can be used as strains), bagged fresh milk, containers for fermented yogurt (capacity150-200g), white sugar, and an incubator (the incubator can be a foamed plastic box for holding birthday cakes). ) and so on are ready for use.

2. Sterilize the container. Boil the water in a clean pot, put the utensils for fermented yogurt in the pot for sterilization, take them out, and put the white sugar while it is hot (generally130g fresh milk with white sugar15g or so).

Step 3 inoculate. Soak the bagged fresh milk in the used boiling water of disinfection utensils for about 5 minutes, so that the temperature reaches about 45 degrees Celsius. Pour the heated bagged fresh milk into the containers for fermented yogurt respectively, and stir to fully dissolve the white sugar in the milk. Inoculate the strains into fresh milk respectively, and then stir evenly. (It is best to use "Danone" pure white yogurt, one cup125g of Danone yogurt, and 2000g of fresh milk can be inoculated. )

4. Pre-fermentation. Seal the inoculated fresh milk with plastic wrap, put it in a self-made incubator, and put a small hot water bag on it to keep the temperature at 35-40 degrees Celsius. Pre-fermentation time: about 7-8 hours in summer and more than 10- 12 hours in winter. You need to change the hot water bottle in the middle of winter. 5. Post-fermentation. After the yogurt is solidified, it can be put in the refrigerator for post-fermentation. After 12 hours, it can be eaten after fermentation. The shelf life of yogurt made in this way can reach about one week, and it can also be used as the seed for making yogurt next time. (Use Danone pure white yogurt as seeds, and keep one cup as seeds at a time, so that you can inoculate for more than 3 times. Friends who like to eat yogurt may wish to give it a try. As long as the utensils are strictly disinfected according to the above requirements, the interference of miscellaneous bacteria in the surrounding environment can be prevented and delicious yogurt can be guaranteed.