The present invention discloses a method for preparing milk-derived angiotensin-converting
enzyme inhibitory peptides by
fermentation with composite strains, which belongs to the fields of microbial technology and
fermentation. The ratio of
whey protein hydrolysate with a molecular weight below 1000 Da and the angiotensin-converting
enzyme inhibition rate in the milk-based
fermentation broth are used as evaluation indicators. The composite strain
Lactobacillus helveticus (
Lactobacillus helveticus , CICC: 20289), composite strain
Pediococcus dilactici (
Pediococcus acidilactici , CICC:20719) were rescreened to obtain strains with excellent
whey protein hydrolysis performance and high angiotensin-converting
enzyme inhibitory peptide production capacity. The two composite strains obtained from the rescreening were enriched and cultured separately, and then inoculated into skim milk
powder culture medium at a specific compound ratio. Through composite fermentation, the angiotensin-converting
enzyme inhibitory peptide content in the milk-based fermentation product was increased. The process of this invention is rationally designed and highly operable. It provides a reference for further increasing the content of
small molecule functional peptides in fermented dairy products, efficiently preparing milk-derived angiotensin-converting
enzyme inhibitory peptides, and improving the nutritional value of dairy products, and has great application prospects.