• 한국식생활문화학회지
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• 제34권2호
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• pp.208-216
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• 2019

Leuconostoc spp. are generally utilized as kimchi starters, because these strains are expected to have beneficial effects on kimchi fermentation, including improvement of sensory characteristics. Here, we developed a detection method for verifying the presence of the kimchi starter Leuconostoc mesenteroides WiKim33, which is used for control of kimchi fermentation. A primer set for multiplex polymerase chain reaction was designed based on the nucleotide sequence of the plasmids in strain WiKim33, and their specificity was validated against 45 different strains of Leuconostoc spp. and 30 other strains. Furthermore, the starter strain consistently tested positive, regardless of the presence of other bacterial species in starter kimchi during the fermentation period. Our findings showed that application of a strain-specific primer set for strain WiKim33 presented a rapid, sensitive, and specific method for detection of this kimchi starter strain during natural kimchi fermentation.

• 동아시아식생활학회지
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• 제23권5호
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• pp.546-560
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• 2013

In this study, a natural fermentation starter formulation was developed for manufacturing Korean bread products by substituting baker's yeast with naturally fermented blueberry starters. As the incubation time of the blueberry extracts increased, the pH and total titratable acidity increased. The sweetness (brix%) of blueberry extracts containing various amounts of sugar were higher than the other sample. The result of alcoholicity for naturally fermented blueberry extracts, the fermented blueberry extract containing 20% sugar was highest. Lactic acid bacteria counts increased until the 4th day; however, it decreased from the 5th day, and viable yeast counts increased consistently until the 5th day. The volume for naturally fermented blueberry extracts increased as the incubation time increased. As the fermentation time of blueberry starters increased, the pH of bread dough decreased. The RVA analysis conveyed that wheat flour retrogradation was retarded by increasing the blueberry starter content. The weight of pan breads containing blueberry starters were higher than that of the control, while the volume, specific volume and baking loss rate were lower than those of the control. The moisture content of pan breads containing blueberry starter decreased as storage time increased. In analyzing the visible mold colony during 7 days of storage at $28^{\circ}C$, mold growth in pan breads containing the blueberry starter was retarded. The hardness of breads containing blueberry starters were significantly increased as storage time increased. The breads containing 50% naturally fermented blueberry starter have acceptable sensory properties. In conclusion, these results indicated that 50% of natural fermentation blueberry starter could be very useful as a substitute for yeast when making naturally fermented bread.

• Journal of Microbiology and Biotechnology
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• 제25권5호
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• pp.559-568
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• 2015

Kimchi is a traditional Korean vegetable product that is naturally fermented by various microorganisms present in the raw materials. Among these microorganisms, lactic acid bacteria dominate the fermentation process. Natural fermentation with unsterilized raw materials leads to the growth of various lactic acid bacteria, resulting in variations in the taste and quality of kimchi, which may make it difficult to produce industrial-scale kimchi with consistent quality. The use of starter cultures has been considered as an alternative for the industrial production of standardized kimchi, and recent trends suggest that the demand for starter cultures is on the rise. However, several factors should be carefully considered for the successful application of starter cultures for kimchi fermentation. In this review, we summarize recent studies on kimchi starter cultures, describe practical problems in the application of industrial-scale kimchi production, and discuss the directions for further studies.

• 한국미생물·생명공학회지
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• 제47권2호
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• pp.234-241
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• 2019

In Korea, traditional doenjang is manufactured using the conventional method at home and by small-scale enterprises. Because this age-old process depends on natural inoculation of various microorganisms, it is difficult to reproduce or maintain consistency in the final product quality across batches. Moreover, doenjang occasionally prepared by this method raises safety concerns related to aflatoxin, biogenic amine, and Bacillus cereus contamination. To develop starters that can be conveniently used at home or in small industry settings for the manufacturing of safe and flavor-improved doenjang, autochthonous microbe starters were developed in dried forms as ready-to-use starters. Each starter powder prepared by heat- or freeze-drying methods remained stable even after 24-week storage. These ready- to-use starter powders were successfully applied to lab-scale fermentation for the production of safe and flavor-improved doenjang. We believe that these ready-to-use starter powders will benefit small-scale enterprises in the manufacturing of doenjang of good reproducible quality.

• 한국축산식품학회지
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• 제36권3호
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• pp.427-434
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• 2016

Benzoic acid is occasionally used as a raw material supplement in food products and is sometimes generated during the fermentation process. In this study, the production of naturally occurring yogurt preservatives was investigated for various starter cultures and incubation temperatures, and considered food regulations. Streptococcus thermophilus, Lactobacillus acidophilus, Lactobacillus delbrueckii subsp. bulgaricus, Lactobacillus rhamnosus, Lactobacillus casei, Lactobacillus paracasei, Lactobacillus reuteri, Lactobacillus plantarum, Bifidobacterium longum, Bifidobacterium lactis, Bifidobacterium bifidum, Bifidobacterium infantis, and Bifidobacterium breve were used as yogurt starter cultures in commercial starters. Among these strains, L. rhamnosus and L. paracasei showed the highest production of benzoic acid. Therefore, the use of L. rhamnosus, L. paracasei, S. thermophilus, and different incubation temperatures were examined to optimize benzoic acid production. Response surface methodology (RSM) based on a central composite design was performed for various incubation temperatures (35-44℃) and starter culture inoculum ratios (0-0.04%) in a commercial range of dairy fermentation processes. The optimum conditions were 0.04% L. rhamnosus, 0.01% L. paracasei, 0.02% S. thermophilus, and 38.12℃, and the predicted and estimated concentrations of benzoic acid were 13.31 and 13.94 mg/kg, respectively. These conditions maximized naturally occurring benzoic acid production during the yogurt fermentation process, and the observed production levels satisfied regulatory guidelines for benzoic acid in dairy products.

• 한국식품저장유통학회지
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• 제20권5호
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• pp.699-704
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• 2013

메밀 속성장은 메밀과 콩으로 제조된 별미장이다. 항균 및 효소활성이 우수한 B. subtilis HJ18-4 균주를 starter로 사용하여 메밀 속성장을 제조하였다. 메밀 속성장 제조과정 중, starter 첨가 시기는 메주 제조단계(Treat-1) 및 염수 첨가단계(Treat-2)로 접종시기를 달리하였다. 발효 중 아미노태질소 함량, 환원당, 효소활성(protease, amylase)의 이화학적 품질특성과 총균 수, 유산균 수 및B. cereus 양 변화 등의 미생물학적 특성을 분석하였다. 그 결과, 총균 수는 발효 15일부터 7~8 log CFU/mL로 증가되었고 아미노태 질소함량은 발효기간 동안 65.38~202.52 mg%로 증가되었다. 반면, 환원당과 효소활성(amylase, protease)은 모든 처리구 에서 감소하였다. 발효기간 중 PlcR 발현에 미치는 영향을 측정한 결과, Treat-1 처리구에서 발효 23일 이후 검출되지 않았다. 메주 제조단계에서 B. subtilis HJ18-4를 접종한 Treat-1이 발효관련 이화학적 특성과B. cereus 저해효과가 우수하였다. 단일 균을 접종하여 제조되는 개량식장 제조 시, 자연발효에 제조된 장의 품질을 재현하기가 매우 어려운 실정이다. 본 연구는 자연발효방법으로 제조되는 메밀 속성장에 항균 및 효소활성이 우수한B. subtilis HJ18-4 균주를 스타터 적용하여 장류 품질개선 방법을 제시하였다.

• 한국유기농업학회지
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• 제22권3호
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• pp.491-502
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• 2014

본 연구는 천연물질에서 유래한 반추위 메탄저감용 친환경 첨가제 개발을 위해 각기 다른 종균을 이용하여 발효한 세신 추출물의 항균활성, 항산화활성 및 in vitro 반추위 발효시험을 체계적으로 실시하였다. 접종된 균주들의 성장효율을 알아보기 위해 실시한 생균수측정 결과 L. curvatus NJ40 균주에서 유의적으로 높은 균주성장을 나타냈다(p<0.05). 항균활성측정 결과는 대조구 대비 L. curvatus NJ40 및 L. plantarum NJ45 균주와 발효된 세신 추출물이 병원균에 대한 항균효과를 나타내는 것으로 조사되었다. In vitro 반추위 발효실험에 세신 및 발효 세신 추출물을 적용한 결과, 휘발성 지방산 생성량 대비 반추위 메탄 저감효과가 나타났다. 특히 반추위 미생물 활력 및 사료이용 효율을 대표할 수 있는 휘발성 지방산 생성효율에 대한 부정적 효과 없이, 오히려 휘발성지방산 생성효율을 향상시키면서 반추위 메탄 저감효과를 가져올 수 있는 것으로 나타났다.

• 동아시아식생활학회지
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• 제18권1호
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• pp.87-94
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• 2008

In this study, a nanatural fermentation starter formulation was developed for manufacturing bread products by substituting baker's yeast with naturally fermented raisin extract and sourdough. Four experimental groups containing 2.5, 5.0, 7.5, 10% naturally fermented raisin extract per 2,000 g of flour were compared based on quality characteristics, including the fermentation power on dough expansion, specific volume, baking loss, water activity, color, textural characteristics, and internal surface appearance. The activities of the naturally fermented raisin extract were examined in terms of pH changes, total titratable acidity, brix, and viable yeast counts. The raisin extract, which was cultured for 7 days at 30$^{\circ}C$, smelled of alcohol and produced $CO_2$. Yeast were also found in the extract after separation. As the incubation time of the raisin extract and sourdough increased, pH decreased, while total titratable acidity increased. The brix of the raisin extract increased until the $2^{nd}$ day of fermentation, and viable yeast counts increased until the $5^{th}$ day however, these gradually decreased by the $7^{th}$ day. The fermenting power on dough expansion increased in the bread with increasing incubation time. The bread samples containing 7.5% and 10% raisin extract had significantly higher specific volumes than the other samples. Baking loss was minimal with the 2.5% extract substitution. In analyzing the crumb, water activity, redness, and yellowness were highest in the 10.0% raisin extract bread samples, and lightness was maximal in the 5.0% group. In terms of textural characteristics, hardness was lowest with the 2.5% extract substitution. Gumminess, springiness, and chewiness were not significantly different among the bread samples. Cohesiveness was highest at the 7.5% extract substitution level, and resilience was lowest at the 10% level. In conclusion, based on the results, a natural fermentation starter formulated with 2.5% naturally fermented raisin extract (1 part raisins and 1.5 parts water) and 70% sourdough (1 part rye flour and 1 part water) has high potential as a baker's yeast substitute for making naturally fermented bread.

• Journal of Microbiology and Biotechnology
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• 제6권6호
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• pp.461-467
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• 1996

Four strains of lactic acid bacteria (LAB), that lower the pH of sausage $\leq$ 4.2 within 24 h of incubation at $37^{\circ}C$, were screened from 57 bacteriocin producing LAB which were isolated from kajamie shikhae and natural fermented sausages. The proteinaceous nature of the bacteriocin was confirmed by losing antimicrobial activity after pronase treatment. Inhibitory activity against pathogens, times of bacteriocin production and sensory tests were compared between 4 isolates and 3 commercial starters. Especially, strain NFS #8-1, screened from natural fermented sausage and identified as Pediococcus acidilactici, antagonized a large number of foodborne pathogens including Listeria monocytogenes, Aeromonas hydrophila, Bacillus cereus, Clostridium perfringens, Salmonella typhimurium and Staphylococcus aureus. Production of bacteriocin by strain NFS #8-1 was early in the growth phase (mid log phase) and its sensory acceptance was high. The feasibility of using strain NFS #8-1 as a starter for the production of microbiologically safe fermented sausage is envisaged.

• Applied Biological Chemistry
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• 제41권6호
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• pp.405-409
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• 1998

본 연구는 재래간장의 원료 대두로부터 자숙과 메주제조 과정중의 당류의 행동을 추적하고 가당에 의한 젖산발효와 알콜발효의 효과를 조사하기 위하여 실시되었다. G8메주와 SB메주 제조과정 중 수용성 당류함량이 대폭 감소하였다. G8메주와 SB메주로 만든 저염간장 소화액에 젖산균 Pediococcus halophilus와 효모 Zygosaccharomyces rouxii 및 Candida versatilis의 종모배양액을 접종한 결과, 5% glucose를 첨가한 G8간장과 SB간장에서는 모두 급속히 젖산발효와 알콜발효가 일어났으나 당 무첨가 간장에서는 발효가 일어나지 않았다. 종모배양액 접종 후 160시간 후 가당 G8간장과 가당 SB간장에서 각각 0.46%, 0.88%의 젖산과 1% 및 약 2%의 알콜을 함유하고 있었다.