Bioactive peptides have good stability and bioavailability, and can achieve efficient formulations, which are highly favored by consumers. Polypeptides have a molecular weight smaller than that of proteins, a simple structure, and are easy to absorb. They have a dual function of regulating physiological functions and providing nutrition to the body. Almost all cells are regulated by peptides, such as cell differentiation, neurotransmitter regulation, signal transduction, and immune response regulation.