Tetragenococcus halophilus MJ4 as a starter culture for repressing biogenic amine (cadaverine) formation during saeu-jeot (salted shrimp) fermentation

Biogenic amines (BAs) are frequently present in traditionally fermented salted foods. In this study, a Tetragenococcus halophilus strain (MJ4) with no BA-producing ability was isolated from a fish (anchovy) sauce. Strain MJ4 did not produce BAs from supplied precursors and no BA-producing genes were identified in its genome. Bacterial community analysis showed that in non-inoculated saeu-jeot (shrimp sauce) fermentation, Tetragenococcus predominated after 82 days, while in strain MJ4-inoculated saeu-jeot, Tetragenococcus predominated during the entire fermentation. Strain MJ4 repressed the growth of T. muriaticus, a known BA producer, during fermentation, but metabolite analysis demonstrated that metabolite profiles, including amino acids, were similar regardless of MJ4 inoculation. The metabolite analysis also showed that strain MJ4 clearly repressed the formation of cadaverine during fermentation. This study suggests that the use of strain MJ4 as a starter culture in salted fish fermentation may be a good strategy for the reduction of BA formation.