성인 남녀의 분변과 시판 요구르트로부터 분리한 10주의 균주들을 밤용액에 접종 발효하고 산생성과 생균수 면에서 각각 우수한 Lactobacillus spp. PAPI과 MGG2를 분리하였다. 발효액의 저장 중 균수는 발효액의 산도에 의존하였고 산도를 낮추었을 때 생균수는 증가하였다. 이들을 혼합 배양하였을 때 발효제품의 산도와 생균수는 각각의 단독배양액에 비하여 더 컸으며 3주간 저장 후 생균수도 100배 이상 컸다. 밤 용액의 발효에서 이들을 상업용 수입 종균제품과 비교하였을 때 24시간 배양에서 생균수가 더 많았다.

Among 10 strains isolated from Korean adult excrements and the commercial yogurt, two stains, Lactobacillus spp. PAP1 and Lactobacillus spp. MGG2, were selected, as the former was best at acid production and the latter at growth in fermented chestnut broth. Viable counts of stored fermented broths were dependent on the acidities of the broths. And the higher the counts, the lower the acidity. The acidity and viable counts of the chestnut broths fermented by mixed cultures were higher than those by each single cultures. After 3 week storage, the viable counts of mixed cultures were 100 times higher than those of single cultures. The selected strains were better than commercial strains in that the selected strains gave more viable counts at 24 hours fermentation.

• 김정숙 | Jung Sook Kim
• 주순재 | Soon Jae Chu