COMPARISON OF VOLATILE COMPONENTS IN SOY- SAUCE (KOIKUCHI-SHOYU) PRODUCED USING ASPERGILLUS-SOJAE AND ASPERGILLUS-ORYZAE

Volatile components contained in raw and pasteurized Japanese soy sauc e of the koikuchi type (koikuchi shoyu) were compared among the produc ts from nine different plants using two different koji molds, Aspergil lus sojae No. 9 (A. sojae No.9) and Aspergillus oryzae S-03 (A. oryzae S-03). Identification of the volatile compounds in koikuchi shoyu and the quantitative comparison were carried out by GC, GC-MS analyses an d the analysis of variance of the GC peak areas. Sixty-five compounds were identified or estimated as koikuchi shoyu volatile components, in which five compounds were newly confirmed or tentatively identified i n koikuchi shoyu. The quantity of A. sojae No. 9 koikuchi shoyu volati les was larger than that of A. oryzae S-03 koikuchi shoyu, and it incr eased when the koikuchi shoyu was heated. 2-Methyl-1-butanol, 3-methyl -1-butanol, ethyl lactate, acetic acid, and 2-phenylethanol, etc., bes ides ethanol, had large peak areas on the gas chromatograms of the koi kuchi shoyu. Ethyl lactate, acetic acid, pyrazines, phenylacetaldehyde , phenol, and maltol, etc., were larger in A. sojae No. 9 koikuchi sho yu than those in A. oryzae S-03 koikuchi shoyu. On the other hand, 2-m ethyl-1-butanol, 3-methyl-1-butanol, 2-phenylethanol, 2-methylbutanoic acid, 3-methylbutanoic acid, 5-methylthio-1-propanol, 2-ethyl-4-hydro xy-5-methyl-3 (2 H)-furanone, 4-ethylguaiacol, and 4-ethylphenol, etc. , were found in abundance in A. oryzae S-03 koikuchi shoyu.