Reduction of Fermentation Time for Preparation of Dongchimi Juice

동치미액 제조를 위한 발효기간 단축 연구

Development of an effective method for the preparation of dongchimi juice was investigated by addition of NaCl, sucrose and hydrolytic enzymes before fermentation and addition of dongchimi juice during fermentation. The Chinese radish was ground and suspended in water (1:1, w/v) with addition of spices of garlic, green onion and ginger followed by fermentation at $25^{\circ}C$. Increase in NaCl concentration of brinning solution from 1.0 to 5.0% resulted in a significant decrease in the rates of pH decrease and acidity increase. The sugar addition resulted in a faster changes of them, particulary after 24 hours at $25^{\circ}C$. The fermentation rate was also greatly improved by enzymatic hydrolysis with using viscozyme, a commercial polysaccharides hydrolyzing enzyme, before fermentation. When the fermented juices of two stage (pH 5.4 and pH 4.4) were added up to 15% before (pH 5.4 juice) and during (pH 4.4 juice) fermentation, the initial and second stage of fermentation were significantly improved. Therefore a method of addition of sugar, hydrolytic enzymes and dongchimi juice before or during fermentation was suggested for dongchimi juice preparation.

동치미액을 속성으로 제조하기 위한 방법을 모색하기 위하여 소금, 항, 당, 효소, 통치미액 첨가가 발효중 동치미액의 pH, 산도에 미치는 영향을 검토하였다. 통치미액은 무분산액에 파, 마늘, 생강을 청가하여 $25^{\circ}C$에서 발효시켰다. $1{\sim}5%$ 소금첨가에서 소금함량이 높아질수록 pH 감소속도가 느렸으며 $0.5{\sim}2.0%$ 설탕의 첨가는 발효 24 시간 이후부터는 빠른 pH 감소를 보였다. 발효전 마쇄무의 효소분해는 viscozyme의 가수분해가 효소 농도가 중가할수록 pH의 감소가 빠르게 진행되었다. pH 5.4 동치미액 첨가와 pH 4.4 동치미액 첨가는 첨가량에는 큰 차이 없이 적당한 신맛을 가지는 pH 4.0으로 떨어지는데 걸리는 시간이 대조구의 절반으로 단축되었다.