Abstract
The formation of β-carboline derivatives during the brewing of soy sauce was examined on a laboratory scale. 1-Methyl-1, 2, 3, 4 tetrahydro-β-carboline-3-carboxylic acid (MTCA) and 1-hydroxymethyl-furyl-β-carboline (1-HMF-BC) were formed largely in the middle and latter stage of brewing, respectively. Both of them were increased by pasteurization. A little 1-furylβ-carboline (1-F-BC) was formed during brewing, and the content was increased by pasteurization. In addition, the changes in β-carboline derivatives during storage at 4, 20 and 30°C for 60 days were examined. MTCA was unchanged after storage. 1-HMF-BC in Koikuchi Shoyu (regular fermented) and Koikuchi Shoyu (semi-fermented) were increased 1.7- and 1.6-fold after storage at 30°C, respectively. Heating did not increase the amount of 1-HMF-BC in soy sauce after storage at 30°C.
