최근, 저온 장시간 발효된 묵은지에 대한 소비가 증가하고 있다. 본 논문에서는, 저온($5^{circ}C$)에서 46주 동안 발효된 묵은지의 pH, 산도, 유기산, 생균수, 아미노산, polygalacturonase (PG) 활성 등을 분석하였다. 10주 발효한 김치에서는 pH 4.1, 산도 0.99%를 나타낸 반면, 46주 발효한 김치에서는 pH 3.9, 산도 1.29%를 보였다. 한편, 10주에서 46주로 발효 기간이 증가하면서, 젖산, 젖산/초산비, Lactobacillus species/Leuconostoc species비 등은 증가한 반면, 호기성 세균, 효모, Lactobacillus species, Leuconostoc species, 유리아미노산, PG 효소 활성은 감소하였다.
Recently, many Koreans have started to consume aged kimchi fermented long-term at low temperatures. In the present study, the effect of low temperature ($5^{circ}C$) on pH, titratable acidity (TA), organic acid level, viable microbial cell count, amino acid concentration, and polygalacturonase activity (PG) during long-term fermentation (46 weeks) of kimchi, were evaluated. After 10 weeks of fermentation, kimchi had a pH of 4.1 and a TA of 1.0%, respectively after 46 weeks fermentation, these values were 3.9 and 1.3%, respectively. Lactic acid, the ratio of lactic acid to acetic acid, and the ratio of Lactobacillus species/Leuconostoc species in kimchi increased as fermentation progressed from 10 weeks to 46 weeks. However, total viable cell counts of aerobic bacteria, yeasts, Lactobacillus species, and Leuconostoc species, free amino acid levels, and PG decreased as the fermentation period was extended from 10 weeks to 46 weeks.
