Unraveling taste enhancement mechanism of yeast-inoculated reduced-salt fermented sausage: Proteolysis, taste compound formation, and receptor binding of potential salty/salty taste-enhancing peptides.

This study investigated the effects of Candida zeylanoides AKS6 and Debaryomyces hansenii AKS44 on the taste profiles of reduced-salt fermented sausage. The inoculation of C. zeylanoides AKS6 and D. hansenii AKS44, particularly for D. hansenii AKS44, enhanced umami-related 5'-nucleotide and lactic acid accumulation in reduced-salt sausages. The sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) analysis indicated that the inoculation with C. zeylanoides AKS6 and D. hansenii AKS44 enhanced proteolytic activity, thus promoting the accumulation of trichloroacetic acid (TCA)-soluble peptides and free amino acids (FAAs), which collectively enhanced umami and salty taste of reduced-salt sausages. Sensory evaluation confirmed notable improvements in overall taste, saltiness, and umami intensity, particularly in D. hansenii AKS44-inoculated sausages. Six novel potential salty/salty taste-enhancing peptides including DDHFLFDKP, DPTPSDGKL, FPPDVGGN, ISEQFTAMFR, PETPPP, VDNPGHPFI were identified exclusively in D. hansenii AKS44-inoculated sausages. Molecular docking demonstrated their strong binding affinity to the transmembrane channel-like protein 4 (TMC4) receptor via hydrogen bonding, with Glu83, Asp86, and His88 as critical interaction sites. This study offers novel insights into the mechanisms underlying salty taste enhancement in reduced-salt fermented meat products inoculated with yeast, thereby providing a scientific basis for developing effective salt reduction strategies.