Enhanced soy sauce stability and reduced precipitation by improving critical steps in the fermentation process

Conventional high-salt dilute-state soy sauce is vulnerable to precipitation after processing, which will reduce the systemic stability and nutrition of soy sauce. This work aims to optimize key steps of the soy sauce fermentation process to improve its stability and reduce precipitation. The amino acid nitrogen (AAN) and the total nitrogen (TN) contents of the new soy sauce were 8.3 g/L and 18.7 g/L, which were significantly enhanced by 33.9% and 14.0%, respectively, compared to the control group. More flavor substances were detected in the new soy sauce, including furans and pyrazines, which contribute to the special flavor of soy sauce. The particle size distribution curve was significantly shifted to the left, and the absolute value of zeta-potential increased. The new fermentation process soy sauce had a higher raw material utilization rate, smaller average particle size of 15.56 μm, and significantly higher stability when combined with the rheological examination. Consequently, the quality and flavor of soy sauce can be improved by using the new fermentation process.