Correlation analysis between the concentration of alpha-dicarbonyls and flavor compounds in soy sauce

Abstract

Soy sauce was fermented with various sterilization temperatures. Among the Maillard reaction products, alpha-dicarbonyl compounds (alpha-DC; glyoxal, methylglyoxal, and diacetyl) and 16 aroma compounds were analyzed, and their correlations were investigated. After fermentation for 8 wk, glyoxal, methylglyoxal, and diacetyl were present in soy sauce at 0.88-2.84, 1.73-3.27, and 0.53-0.86 mu g/ml, respectively. Among the 16 aroma com-pounds, acetic acid dominated and showed the largest change with the sterilization temperature. The quantities of alpha-DC and volatiles showed a strong positive correlation (maximum r = 0.912) with the sterilization tem-perature. To reduce the levels of alpha-DC in soy sauce, a 60-70 degrees C sterilization temperature is proposed. Partial least squares regression was done to investigate the aroma compounds affecting the formation of alpha-DC. Among the volatile compounds analyzed in this soy sauce model system, 1-octen-3-ol was the most likely determinant of alpha-DC content.