Lipase Addition Promoted the Growth of Proteus and the Formation of Volatile Compounds in Suanzhayu, a Traditional Fermented Fish Product

This work investigated the effect of lipase addition on a Chinese traditional fermented fish product,Suanzhayu. The accumulation of lactic acid and the decrease of pH during the fermentation were mainly caused by the metabolism ofLactobacillus. The addition of lipase had little effect on pH and the bacterial community structure but promoted the growth ofProteus. The addition of lipase promotes the formation of volatile compounds, especially aldehydes and esters. The formation of volatile compounds is mainly divided into three stages, and lipase had accelerated the fermentation process.Lactobacillus,EnterococcusandProteusplayed an important role not only in inhibition of the growth ofEscherichia-Shigella, but also in the formation of flavor. This study provides a rapid fermentation method for theSuanzhayuprocess.Keywords:fermented fish;Proteus;lipase;volatile compounds;aldehydes;esters