Effect of starter cultures and spices on physicochemical properties and microbial communities of fermented fish (Suanyu) after fermentation and storage

Suanyu is one of the traditional Chinese fermented fish products with a pleasant flavor. The present study sought to evaluate the effects of starter cultures and spices on the physicochemical properties and microbial flora of Suanyu after fermentation and storage. The results indicated that fermentation with mixed starter cultures could lower the pH and inhibit TVB-N formation in Suanyu after fermentation and during storage. Moreover, inoculation of starter cultures could promote free amino acids production during storage. Additionally, inoculation of mixed starter cultures and spices mixture could effectively inhibit the formation of most biogenic amines in Suanyu, revealing the significant role of mixed starter cultures. Staphylococcus, Macrococcus, and Lactobacillus were the core microbial genus in Suanyu. The inoculation of starter cultures could inhibit Enteroccoccus and other microorganisms, while spices introduced Bacillus into Suanyu. The study results provide a theoretical basis for the industrial production and storage of Suanyu.