Screening of flavor-presenting lactic acid bacteria from naturally fermented seafoods

Abstract

In this study, ten high protease-producing isolates were selected from a total of 163 isolates obtained through the isolation and purification of fish sauce, shrimp paste, eel paste, and Dai Shan pickled fish. A total of 6 isolates were subjected to screening based on their bacteriostatic and acid-producing capabilities. Finally, two excellent strains of Lactiplantibacillus plantarum DZ3–1 and Companilactobacillus alimentarius DZ3–6, which significantly improved the flavor of fermented seafood, were screened by branched-chain aminotransferase activity, nicotinamide adenine dinucleotide-Glutamate dehydrogenase activity, optimal growth conditions, and fish isolated soluble protein (FISP) fermentation experiment. The results showed that L. plantarum DZ3–1 and C. alimentarius DZ3–6 had higher flavor enzyme activity. Both DZ3–1 and DZ3–6 have 2 flavor compounds (1-Penten-3-one and 3-methyl-Butanoic acid) with OAV values > 1, suggesting that these compounds contributed significantly to the overall flavor of the fermented FISP. 3-methyl-Butanoic acid was identified in all samples except the fermentation DZ3–7 group. It may be a flavor compound produced by the metabolism of branched-chain amino acids by 2 flavor enzymes.