Changes in the mutagenicity of soy sauce upon heating, and determination of .BETA.-carboline derivatives.

Abstract

25 brands of soy sauce were determined by high-performance liquid chromatography.The concentration of MTCA in Koikuchi Shoyu (regular fermented) and Koikuchi Shoyu (semi-fermented) was 486 (mean) and were increased.Soy sauce was mutagenic to S. typhimurium TA100 without S-9 mixture before and after nitrite treatment.The mutagenic activities of Koikuchi Shoyu (regular fermented) and Koikuchi Shoyu (semi-fermented) were 21,000 (mean) and 13, 900 (mean) His+ revertants/ml, respectively. The mutagenic activities were increased by heating in both cases before and after nitrite treatment.The relationship between the contents of MTCA and 1-F-BC and mutagenicity is also discussed.