Tetragenococcus halophilus A003, an indigenous strain found in fish sauce, was added to the fermentation process. It successfully enhanced low BA-producing microbes, reducing bioamine accumulation in the final product. This method improves the safety of fermenting protein-rich feedstocks.
Fish sauce, a seasoning commonly utilized in East Asian cuisine, is produced from fish combined with a substantial quantity of salt. However, biogenic amines (BAs) accumulation poses safety concerns in fermented fish sauce during fermentation. This study characterized Tetragenococcus halophilus A003, isolated from fish sauce, which exhibited the weakest decarboxylase gene activation and lowest BA production among the tested strains. Starter inoculation with A003 yielded minimal chemical alteration compared to natural fermentation.  Cadaverine levels were substantially lower (19.1 ± 1.49 mg/L) than those in sauce fermented without a starter or with T. halophilus BCRC12250. Histamine and tyramine were undetectable in isolate A003-inoculated samples. Metagenomic analysis revealed an enrichment of low BA-producing taxa, notably Tetragenococcus and Staphylococcus, comprising 97.91% of the community. These findings suggest T. halophilus A003 confers a selective advantage for low BA microbiota during fish sauce fermentation