Screening and Characterization of novel umami peptides in Cheddar cheese using peptidomics and bioinformatics approaches

Cheese is the potential great source of umami peptides, while studies on umami peptides in cheese are scant and current sensory-guided strategies are difficult for rapid and high-throughput screening umami peptides. Herein, the peptidomics of Cheddar cheese was conducted and 6 potential umami peptides (LEEL, EKNRLNFLK, DERF, NAVPITPTLNREQ, NMAINPSKENL, GKEKVNELSK) were screened by an integrated bioinformatics approach. Peptides except LEEL were validated as umami peptides while LEEL and DERF exhibited significant umami-enhancing effects. Molecular docking revealed that hydrogen bonds formed by hydrophilic amino acids between peptides and T1R1/T1R3 are critical for the binding of umami peptides to umami receptors. Furthermore, Phe247, Gln278 of T1R1 and Pro106 of T1R3 were inferred as key binding sites. In silico gastrointestinal digestion indicated that peptides except DERF have hypoglycemic and hypotensive potential. This work lays the foundation for high-throughput umami peptide screening and advances to understand the umami mechanism of cheese.