Postbiotics are a new means of intervention in the intestinal ecosystem that has emerged in recent years. Postbiotics refer to soluble factors (products or metabolic by-products) secreted by living bacteria or released after bacterial lysis, namely small molecules that regulate the health of the host, such as enzymes, peptides, teichoic acid, peptides derived from peptidoglycan, polysaccharides, cell surface proteins, and organic acids. Although the International Symposium of the International Scientific Association for Probiotics and Prebiotics has not yet published a consensus on postbiotics, this concept closely related to probiotics still attracts people’s attention. This paper briefly clarifies the classification and preparation methods of postbiotics, and discusses the advantages and potential application of postbiotics as functional ingredients in dairy products.

Protein is an important nutrient for human health, and milk protein is considered an important source of natural bioactive peptides. Milk-derived bioactive peptides, mainly derived from casein and whey proteins by enzymatic hydrolysis or microbial fermentation, contribute to the development of human nervous, gastrointestinal, cardiovascular and immune systems and play a vital role in preventing cancer, osteoporosis, high blood pressure and other health problems. In this paper, the application of milk-derived bioactive peptides in nutraceuticals and functional foods has received more and more attention. This article summarizes the production technologies and biological activities of milk-derived bioactive peptides, and provides an outlook on the future production and application of milk-derived bioactive peptides.

Bovine milk is known as the “white blood” and is one of the most ideal natural foods, rich in protein, milk fat, calcium, vitamins and the eight essential amino acids, also known as a near-perfect food. However, in China, cow’s milk is mostly used for liquid milk processing, and its nutritional value has not been fully utilized. Casein gene polymorphisms are thought to affect milk yield, physicochemical properties and nutritional composition, dairy product manufacturing performance and nutrition, and hence have received much attention from scholars. In this paper, we summarize the existing studies on casein gene polymorphism, the methods used for its detection, and its application, hoping to provide some reference for the targeted breeding of dairy cows, the improvement of milk quality, and the precise development of functional dairy products.