Milk is one of the beverages that we consume regularly in our daily life and casein in milk is a very interesting component. Casein is a whey protein and is one of the most abundant proteins in milk. It is a mixture of several different proteins, including αs1-casein, αs2-casein, β-casein and κ-casein. The amount and proportion of each protein varies depending on the breed of cattle, feeding practices and other factors.

Caseins play an important role in milk. They form the gluey consistency and elasticity that gives milk its milky nature. In addition, caseins help maintain the stability of milk and protect protein and fat molecules, thus preserving the quality of milk. Nutritionally, casein is a high-quality protein with high absorption and nutritional value. For this reason, casein is also an important ingredient in many health and nutritional supplements.

Because of its special properties and nutritional value, casein has been widely used in the food industry and in the field of medicine and health care. In the food industry, casein can be used in the production of cheese, cream, yogurt and other dairy products. In the field of medicine and health care, casein can be used to produce nutritional supplements, protein drinks and other products. In addition, casein is also used in the preparation of nanomaterials, semiconductor materials, functional coatings and other fields, which has become one of the hot spots of today's materials science research.