Fermentation temperature has some effects on the surviving enzyme activity and then the flavor composition of soy sauce. The effects were studied and by adjusting fermentation temperature and salt content the quality situation of soy sauce was improved. The paper showed that: 1. Low temperature at pre-stage was benefit to the preservation of enzymes activity, but the low temperature would also reduce the rate of enzymatic reaction. Although the total nitrogen content of the experimental group was lower than the blank group, but the amino nitrogen formation rate was higher than the blank, which indicated that pre-stage low-temperature fermentation was benefit for the conversion of total nitrogen to amino nitrogen. 2. By the free amino acid analysis, the delicious amino acids content of the two-stage fermentation experimental group with 15% salt content was 7.949mg/ml, which increased 21.42% compared with the control. The content of bitter taste amino acids was 5.574mg/ml, which decreased 20.12% compared with the control. 3. The two-stage improving fermentation process was performed as: first stage fermentation at 45℃ for 15d, second stage at 30℃ for 10d, the total fermentation period was 25d. Compared with the traditional process the content of the delicious amino acids was increased 21.58% and the content of the bitter taste amino acids was decreased 21.61% compared with the control. The total sugar and reducing sugar content were also higher than the control. This showed the new process technique would be possibly fit in with the industrial process.
Relationship between fermentation temperature, enzyme activity and flavor composition of soy sauce, and its possibil application[J]. China Brewing, 2012, 31(12): 20-26