Dynamics of bacterial composition and association with quality formation and histamine accumulation during Antarctic...

In this study, we first verified the feasibility of using Antarctic krill as a raw material for quick-brewed fish sauce, and the results showed that the amino acid nitrogen (AAN)and total soluble nitrogen(TSN) in the fermented 30 days fish sauce met the national level fish sauce standards, but the histamine content exceeded the maximum limit value of histamine in fish sauce (400 mg/kg) set by the International Codex Alimentarius Commission (CAC) and the European Union (EU). On this basis, the correlation between physicochemical indexes and bacterial communities during the fermentation of fish sauce was investigated using high-throughput sequencing, culture method. The correlation analyses revealed the relationship between bacterial communities and the quality and safety of fish sauce, and these studies will be helpful for the development of Antarctic krill fish sauce. The results showed that Staphylococcus were positively correlated with the accumulation of histamine and TVB-N during fermentation. This may be due to the presence of genes encoding histidine decarboxylase in Staphylococcus. Virgibacillus was positively correlated with the accumulation of AAN during fermentation. It was also found that Virgibacillus dokdonensis had a high protease activity (153.22 U/mL) and Staphylococcus epidermidis was the most capable of producing histamine at 31.59 mg/kg. Therefore histamine can be reduced by adding bacteria that inhibit the growth of Staphylococcus or degrade histamine as a fermenter.