The quality Comparison of Uncleaned Rice Vinegar by Two Stages Fermentation with Commercial Uncleaned Rice Vinegar

2단계 발효에 의한 현미식초와 시판현미식초의 품질 비교

A vinegar was prepared from uncleaned rice by two step fermentation, alcohol fermentation followed by acetic acid fermentation. The contents of alcohol reached to 10.8% during the alcohol fermentation of uncleaned rice with nuruk, and acidity reached to 5.78% during the acetic acid fermentation. Acidity and pH of vinegar of two step fermentation were higher than those of commercial vinegars. 'L' value(Light) of the vinegar was lower, 'a' and 'b' value were higher than those of commercial vinegars. The contents of acetic acid, malic acid, citirc acid and tartaric acid were hish in organic acid of vinegars. The content of each ofganic acid in vinegars was remarkably different. The content of free amino acids was 2199.7${\mu}\ell$/ml in the vinegar produced by two step fermentation which is higher than that of others.

알콜발효 및 초산발효의 2단계 발효에 의해 현미식초를 제조하였을 때 1단계 알콜발효의 알콜 함량은 10.8%이었고, 2단계 초산발효의 총산함량은 5.78%이었다. 2단계 발효 현미식초의 산도와 pH는 시판 현미식초에 비해 높았고, 색도 중 명도는 4개사의 제품보다 낮았고, 적색도와 황색도는 반대현상이다. 유기산의 함량은 acetic acid 이외에 malic, citric acid, tartaric acid의 함량이 높았으며, 각 유기산의 함량은 제품에 따라 상당한 차이가 있었다. 2단계 발효식초의 총 유리아미노산 함량은 2199.7${\mu}\ell$/ml이었으며, 시판 4개사의 제품보다 뚜렷하게 높았다.