There are four kinds of yogurt. According to the nutritional value of yogurt, yogurt includes sour milk, fermented milk, flavored sour milk and flavored fermented milk. The selection basis is as follows:

1. It is best to choose fermented milk, because the nutritional value of fermented milk is higher than that of yogurt, and the added fruit in flavored yogurt or fermented milk is not as good as the added fresh fruit;

2. It is better to choose yogurt with a shelf life of 14 days, because the yogurt with a shelf life of 21 days may be added with preservatives to extend the shelf life, or other methods are adopted;

3. From the milk source of pure milk in yogurt, it is important to choose the milk source from organic pasture, because milk is rich in vitamins and minerals needed by human body, which is of great significance to human health;

4. As far as the sterilization method of yogurt is concerned, we generally choose pasteurized milk. Pasteurization, also known as low-temperature sterilization and cold sterilization, is a sterilization method that can kill germs and keep the flavor of nutrients in articles unchanged at a low temperature, and is often widely used to define heat treatment methods that need to kill various pathogens. The nutritional value of yogurt is preserved to the greatest extent.