Influence of three kinds of protein raw materials on quality of soy sauce

Soybean meal, cottonseed cake and rapeseed meal were applied as the main protein raw materials for soy sauce fermentation and bran was selected as starch materials. The brewing experiments involve natural drying method and solid low-salt fermentation method in laboratory, and pre-mix seeds in the fermentation brine concentration are set as 0, 6.0%, 13.5%, and 24.6 % four salinity gradient. When the fermentation is over, 24 samples of soy sauce show out. The conclusion was drawn by sensory evaluation and physico-chemical determination: the quality of soy sauce brewed by laboratory low-salt solid insulation is superior to natural sun-brewed soy sauce; for the same raw materials and the same fermentation process, the soy sauce reach to best quality when salt concentration is 13.5% (ie, 13°Be) ; the order of three protein materials contribute to the quality of soy sauce was as follows: soybean meal, rapeseed meal, cottonseed cake.