Abstract: Animal milk has become the major source of bioactive peptides due to its high contents of proteins and essential amino acids, high yield and good stability. Bioactive peptides are encrypted and inactive in the parental proteins, so they must be released to show their biological activity. Depending on their amino acid compositions, sizes, sequences, and physicochemical properties, bioactive peptides can exert angiotensin converting enzyme (ACE) inhibitory, antioxidant, antibacterial, antithrombotic, or immunomodulatory effects. Microbial fermentation is an effective method to prepare bioactive peptides. In this paper, the research progress in the preparation of milk derived bioactive peptides by microbial fermentation is reviewed, the diversity of bioactive peptides produced by different microbial proteases is clarified, and future trends for the preparation of bioactive peptides by microbial fermentation are discussed. This review is expected to provide a theoretical basis for the development and utilization of milk derived bioactive peptides in the future.

Key words: milk; bioactive peptide; microbial fermentation