The impact of protein hydrolysis on biogenic amines production during sufu fermentation

This research was investigated the effects of different degrees of protein hydrolysis on formation of biogenic amines (BAs) during sufu fermentation. Proteolysis indicators and physicochemical parameters of sufu have been determined. Moreover, 7 BAs were detected using high performance liquid chromatography (HPLC). These results showed that the total BAs increased to the maximum of 318.59 mg/kg on 84 days of ripening. The physical indicators achieved the national standard, and pH ranged from 5.95 to 6.97 which could effectively prevent the formation of BAs by reducing the activity of decarboxylases. Proteolysis indicators, the contents of neutral proteases and basic proteases, increased on 28 days of ripening then decreased lightly during ripening period. For amino acid decarboxylase (AAD), maximum level of 151.65 IU/L was attained in the end. It showed a similar trend with the content of total BAs. The Pearson correlation analysis indicated that some BAs were positively correlated with protein metabolism ( P < 0.05). It is an effective way to control the formation of BAs through reducing the activity of decarboxylases. These findings could expand the understanding for mechanisms of proteolysis on formation BAs and provide further knowledge to control the BAs, which could enhance the safety and quality of sufu. • The total biogenic amines increased to the maximum at the end of fermentation. • The content of amino acid decarboxylase showed a fluctuating upward trend. • Histamine was positively related with peptides and amino acid decarboxylase. • The physical indicators achieved the national standard.