Recently, many studies have shown that propolis has diverse health beneficial effects such as anti-cancer, anti-bacterial, anti-inflammation, and anti-oxidant activities. Water-insolubility of propolis has made it extremely difficult in manufacturing health beneficial beverages containing propolis. In this study, the solubility of propolis was dramatically improved by entrapping with beta-cyclodextrin and the prebiotics effect of water-soluble propolis on the yogurt fermentation was investigated. Lactobacillus pentosus SC60 was selected as a starter for the yogurt fermentation due to its high DPPH radical scavenging activity. Low-fat milk which was supplemented with different concentrations of propolis (0.01, 0.05, 0.1, or 0.5% (w/v)) was fermented with L. pentosus SC60 for 30 h and the viable cell number, pH, and titratable acidity were checked. The rates of decrease in pH and increase in titratable acidity of yogurt after 12 h of fermentation were the highest when 0.5% (w/v) propolis were supplemented. Meanwhile pH and titratable acidity of yogurt without propolis reached 4.54 and 0.73%, respectively, most slowly after 30 hoffer mentation when compared with other yogurts supple mented with propolis. The viable cell number of L. pentosus SC60 in yogurt with 0.5% (w/v) propolis increased with highest rate and it exceeded 9 log CFU/mL at 8 h of fermentation, but that of yogurt with no propolis was only 8.54 log CFU/mL at 30 h of fermentation. This results showed that L. pentosus SC60 grew very well in the presence of water-soluble propolis and it is proposed that propolis acts as prebiotics

팽이버섯 내에 존재하는 GAD 효소를 발효를 통해 활 성화 시켜 MSG를 GABA로의 전환율을 높이고자 하였다. 효과적인 고농도 GABA를 생산하기 위해 나노분말 팽이 버섯에다가 수경재배한 인삼을 첨가하여 야쿠르트발효기 에서 발효한 결과 GABA 전환율은 팽이나노인삼분말 발 효군(88%) > 팽이분말 발효군(52%) > 팽이나노분말 발 효군(44%) 순으로 나타났다. 이러한 결과는 MSG를 기질 로 첨가하는 식품에서 활용할 가치가 있으리라 사료된다.

본 연구에서는 단백질이 풍부한 원료 콩에 청국장에서 분리한 Bacillus subtilis와 김치에서 분리한 Lactobacillus plantarum을 이용한 혼합발효를 통해 대두 발효 제품의 개발을 목표로한 연구결과는 다음과 같은 분석 결과를 얻었다. 우수 균주 선별을 위한 연구로 고초균의 경우 단백질 분해능이 높은 균주를 청국장에서 분리하였고, 유산균의 경우 산도 생성이 높은 균주를 김치에서 분리하였다. 그리고 청국장에서 분리한 균주는 Bacillus subtilis로, 김치에서 분리한 균주는 Lactobacillus plantarum으로 동정되었다. 두유 발효에서 pH는 Lactobacillus plantarum를 이용한 두유 발효와 혼합 배양의 경우가 급격한 낮은 경향을 나타내었고, Bacillus subtilis 단독 배양일 경우가 다른 처리구에 비해 완만한 변화를 보였다. Lactobacillus plantarum을 이용한 두유 발효와 혼합 배양의 경우가 lactic acid의 생성은 배양 8시간 이후에 급격히 증가하였으며, Bacillus subtilis 단독 배양의 경우가 완만하게 증가한 경향을 나타내었으며, 이는 pH 분석에서 나타난 결과와 일치하였다. 두유 요구르트 생육도 측정 결과는 혼합 배양의 경우 단독배양에 비해 증식이 더 우수하였으며, 배양 32시간째 각 처리구별 총 균수는 Lactobacillus plantarum의 경우 1.02×108 cfu/㎖, Bacillus subtilis의 경우 2.12×108 cfu/㎖인데 비해 혼합 배양의 경우는 4.09×108 cfu/㎖로 가장 높았다. α-Amylase의 활성은 Bacillus subtilis 단독 배양과 혼합 배양일 경우는 8시간 이후 효소 활성이 증가되면서 24시간 동안 발효시 22.01 unit/㎖, 8.13 unit/㎖로 가장 높았다. Protease의 경우는 Bacillus subtilis 단독 배양과 혼합 배양일 경우는 8시간 이후 활성이 증가하기 시작하여 발효 32시간째 103.08unit/㎖, 85.84 unit/㎖로 활성이 높게 나타났다, Lactobacillusplantarum 단독 배양일 경우는 가수분해효소 활성이 없는 것으로 나타났다.

The principal objective of this study was to investigate the influence of buckwheat sprouts on the acid production and growth of lactic acid bacteria in to which 5 and 10%(w/v) buckwheat sprouts was added, followed by fermentation with Lactobacillus bulgaricus. In yogurt to which 5 and 10% buckwheat sprouts was added, pH was lower and titratable acidity was higher than those of the control. It was also noted significant changes in the number of viable cell counts with differing amounts of added buckwheat sprouts until 12 hours. When the yogurt samples were stored for 12 days at 4℃, the pH and titratable acidity of the yogurt to which 5 and 10% buckwheat sprouts was added were maintained at lower and higher than control levels, respectively. The highest number of viable cell counts was found in the yogurt to which 5% buckwheat sprouts was added. Rutin content was reduced via lactic acid fermentation, but quercetin content increased significantly in the yogurt with added buckwheat sprouts. It may be that the glycosidic bonds connected to rutin were hydrolyzed during fermentation by lactic acid bacteria. The total phenol compound content of the yogurt samples also increased after fermentation. The antioxidative activity of yogurt to which 10% buckwheat sprouts was added was shown to have a 60.95% free radical scavenging effect, which was the highest among all yogurt samples evaluated.

This study was perfomed to determine the feasibility of developing a healthy yogurt using tofu whey concentrates separated by nanofiltration (NF). The curd yogurt was prepared from whole milk with added skim milk powder, in which the NF powder was substituted at 0, 6.25, 12.5, or 25% for the skim milk powder. The quality characteristics were evaluated for pH, titratable acidity, viscosity, color, and viable cell counts. There were no significant differences in pH or titratable acidity between the control (yogurt with added skim milk powder only) and the yogurts with added NF powder, after 24 hr of fermentation at 370C. The apparent viscosities of the yogurts with added NF powder were higher (3,197~3,574 cps) than that of the control yogurt (3,196 cps). Lightness decreased, while yellowness increased, as the amount of NF powder increased. Sensory evaluations showed that the NF powder could be substituted for the skim milk powder at 6.25% without lowering the yogurt quality.

Baechu kimchi without cuttlefish (control), baechu kimchi with cuttlefish (CK), cuttlefish baechu kimchi with yogurt (CK+Y), and cuttlefish baechu kimchi with vitamin C (CK+VC) were prepared, and the fermentation characteristics of the prepared kimchi samples were investigated during 28 days of fermentation at 4℃. The levels of moisture, crude lipid, and crude ash did not differ much among the samples, but the crude protein levels of CK, CK+Y, and CK+VC were greater than that of the control. The pH values of CK+Y and CK+VC slowly decreased compared with those of the control and CK during fermentation. The acidity increased sharply until 21 days then gradually increased thereafter. The total microbial counts achieved maximum levels at 21 days, and the kimchi to which yogurt and vitamin C were added showed values lower than that of the control. The number of Leuconostoc sp. in CK+Y and CK+VC was higher than that in the control. In our sensory evaluations, cuttlefish kimchi with yogurt or vitamin C scored highest in terms of texture, sour taste, ripened taste, and overall acceptability.