Volatile Flavor Components in Mash of Takju prepared by using Rhizopus japonicus Nuruks

Rhizopus japonicus 누룩으로 담금한 탁주 술덧의 발효 과정 중 휘발성 향기성분

Volatile flavor components in the mash of takjus prepared by using Rhizopus japonicus nuruk were identified by using GC and GC-MS. Twenty-four esters, 19 alcohols, 9 acids, 10 aldehydes and 4 others were found in the mash of takju. Thirty nine components including 14 esters and 12 alcohols were detected in the beginning of fermentation. Seventeen components were more detected after second day of fermentation and 66 components were detected after 12 days of fermentation. Thirty eight flavor components including 12 alcohols such as ethanol, 2-methyl-1-propanol and 3-methyl-1-butanol, 14 esters such as ethylacetate, ethylcaprylate and isoamylacetate, 6 aldehydes and 5 acids were usually detected in the fermentation process. Ethanol was predominantly found in the range of 76.2149-92.1155% as a major component by using relative peak area. 3-Methyl-1-butanol, 2-methyl-1-propanol, ethyl caprylate, 2,3-butanediol and benzeneethanol were some of the major volatile components through the fermentation. Peak area of ethylacetate, diethyl succinate, octanoic acid, acetic acid and isobutylaldehyde among the same group were higher than other component depending upon fermentation time.

Rhizopus japonicus균을 파종하여 만든 누룩으로 담금한 탁주 술덧의 발효과정 중 휘발성 향기성분을 GC와 GC-MS를 사용하여 분석 동정한 결과 ester 24종, alcohol 19종, acid 9종, aldehyde 10종, 기타 4종 등 66종의 향기 성분이 동정 되었다. 동정된 향기성분 수는 담금일에 ester 14종, alcohol 12종을 비롯한 총 39종 이었으나, 발효 2일에 ester 6종, alcohol 4종을 포함한 17종이 추가 검출되어 56종으로 증가 되었다. 발효 12일에는 66종으로 향기 성분수가 최대에 달하였다. ethanol, 3-methyl-1-butanol, 2-methyl-1-propanol등 alcohol류 12종, ethyl acetate, ethyl caprylate, isoamyl acetate 등 ester류 14종 acetaldehyde 등 aldehyde 6종, pentanoic acid 등 acid 5종등 총 38종은 발효 전과정을 통하여 검출되었다. 향기 성분의 면적비율은 ethanol이 $76.2149{\sim}92.1155\;%$로 발효 전기간을 통하여 탁주 술덧에서 타 성분 보다 월등히 높았다. ethanol을 제외하고 발효 전과정을 통하여 면적비율이 높은 성분은 3-methyl-1-butanol, 2-methyl-1-propanol, ethyl caprylate, benzene-ethanol, 2,3-butanediol이었다. 이외 발효기간에 따라서 ethyl acetate, diethyl succinate, octanoic acid, acetic acid, isobutyl aldehyde 등의 성분도 동종 계열간의 향기 성분중 면적비율이 높게 나타나기도 하였다.