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

Abstract

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 of Lactobacillus. The addition of lipase had little effect on pH and the bacterial community structure but promoted the growth of Proteus. 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, Enterococcus and Proteus played an important role not only in inhibition of the growth of Escherichia-Shigella, but also in the formation of flavor. This study provides a rapid fermentation method for the Suanzhayu process.

Characteristics of Lactic Acid bacteria isolated from traditional fermented fish

“…Lipase is an enzyme that hydrolyze triacylglyceride to diacylglyceride, monoglycerides, fatty acid and glycerol. Lipase can develop a unique aroma during food fermentation, such as fermented milk (Shojaei Zinjanab et al 2021), a fish fermented, shuanzhayu (Jiang et al 2021). Protease activity contribute to protein degradation by causing flesh breakdown in fish fermentation.…”

Changes in Key Aroma Compounds and Esterase Activity of Monascus-Fermented Cheese across a 30-Day Ripening Period

“…Monascus possesses various esterases, proteases, and lipases that can be excreted to the extracellular space to accelerate the hydrolysis of protein and fat in dairy products. The role of protease and lipase in accelerating cheese ripening and promoting the formation of aroma compounds has been extensively studied [ 13 , 14 ]. The use of esterases in the cheese production process, together with a milk-clotting preparation technique containing a certain ratio of proteolytic enzymes (chymosin/pepsin), has been proven to positively affect the sensory properties and shorten the maturation time of cheeses [ 15 ].…”

Screening of Lactiplantibacillus plantarum with High Stress Tolerance and High Esterase Activity and Their Effect on Promoting Protein Metabolism and Flavor Formation in Suanzhayu, a Chinese Fermented Fish

“…Suanzhayu is a dish made with freshly caught grass carp. The carp were de-headed, de-tailed, and gutted, then cut into pieces and mixed with rice flour, salt, and spices (methods vary by region) and layered into a filled jar for fermentation [2,[16][17][18]. Natural fermentation, on the other hand, is now primarily used, which has a long fermentation cycle, inconsistent quality between batches, and insufficient flavor production.…”

“…Natural fermentation, on the other hand, is now primarily used, which has a long fermentation cycle, inconsistent quality between batches, and insufficient flavor production. Suanzhayu's current research focuses on the relationships between physicochemical property changes, microbial structure evolution, and volatile flavor compounds during fermentation [17,[19][20][21]. Suanzhayu starter cultures, particularly those that promote the synthesis of ester compounds, are still uncommon.…”