• Food Science and Biotechnology
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• 제16권6호
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• pp.994-998
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• 2007

Changes in microflora, pH, reducing sugar content, lactic acid content, and ethanol content during Korean rice wine fermentation were investigated. Typical quality characteristics of Korean rice wine fermentation including pH, reducing sugar content, lactic acid content, and ethanol content were evaluated. While a fungus was not detected in our Korean rice wine mash, yeast was found to be present at fairly high quantities (1.44-4.76\;{$\times}\;10^8\;CFU/mL$) throughout the fermentation period. It is assumed that lactic acid bacteria (LAB) had effects on the variations of fragrance and flavor for traditional Korean rice wine. The main LAB during the Korean rice wine fermentation was determined and identified as a Gram-positive, straight rod-shaped cell. Genotypic identification of the isolated strain by amplification of its 16S rRNA sequence revealed that the isolated strain was most closely related to Lactobacillus plantarum (99%) strains without any other comparable Lactobacillus strains. Therefore, we designated the major LAB identified from traditional Korean rice wine fermentation as L. plantarum RW.

• 한국식품영양과학회지
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• 제41권12호
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• pp.1693-1700
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• 2012

본 연구는 흑미를 첨가하여 막걸리를 제조하여 항산화 및 발효특성을 살펴보았다. 항산화 활성은 대조구에 비해 흑미 첨가구가 높았으며 특히 DPPH 라디칼 소거능은 안토시아닌 함량과 비례하였다. 발효 3일째, pH는 급격히 감소하였으며 대조구에 비해 흑미 첨가구가 낮았다. 환원당과 유리당은 1일째 급격히 증가하였다가 그 이후 감소하는 경향을 나타내었는데 이는 발효 초기에 당화 효소 활성으로 쌀의 전분이 glucose와 maltose 등으로 분해되기 때문이다. 모든 유기산은 발효 동안 증가하였으며 lactic acid가 가장 높은 증가율을 나타내었다. 발효 동안 흑미 첨가 막걸리의 lactic acid와 succinic acid는 대조구와 큰 차이를 보이지 않았다. 발효 초기 젖산균수가 증가하여 3일째 최대에 달하였으며 이는 lactic acid가 급증한 시기와 일치하였다. 또한 흑미 첨가량이 많을수록 젖산균수가 높았다. 색도는 흑미의 붉은색의 영향으로 대조구에 비해 흑미 첨가구의 a값이 높았다. 관능검사 결과 외관은 흑미 첨가구가 높은 점수를 받았으나 전체적으로 단맛과 신맛의 영향을 받아 대조구와 20% 첨가구를 선호하는 것으로 나타났다. 흑미를 첨가할수록 항산화 성분은 증가하나 관능평가 결과로 보았을 때 흑미는 20% 수준 첨가하는 것이 바람직한 것으로 나타났다.

• Preventive Nutrition and Food Science
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• 제16권2호
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• pp.142-149
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• 2011

The purpose of this study was to elucidate the physicochemical and microbiological properties of Korean traditional rice wine, Makgeolli, supplemented with black garlic extract during fermentation. Black garlic extract was diluted with distilled water to produce 0.5% and 1.0% black garlic solutions. Those solutions were then used to make rice solutions which included 2 kg rice, 40 g Nuruk (a fermentation starter), and 14 g yeast. After being mixed, the rice solutions were fermented for 7 days in a water bath at $28^{\circ}C$. The alcohol contents of the control, 0.5% and 1.0% black garlic Makgeolli were 16.9, 16.0, and 16.2%, respectively. Total acidity, total soluble solids, and color increased throughout the fermentation process. There was an increase of microorganisms throughout the fermentation period in all the samples. Glucose was the highest free sugar, and succinic acid was the highest organic acid detected in all the samples. Thirty nine volatile compounds were detected in black garlic Makgeolli.

• Mycobiology
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• 제38권2호
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• pp.122-127
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• 2010

Different strains of mold were screened for the production of high quality Korean traditional rice wine with anti-hypertension and good acceptability. We isolated 867 nuruk mold strains and selected 24 for further study based on measurement of amylase activity. Among them, mold No. 17 showed high ethanol production upon fermentation with Saccharomyces cerevisiae as well as anti-hypertensive properties. The No. 17 strain was therefore selected as the functional mold and later identified as Rhizopus stolonifer based on molecular biological characteristics. Optimal fermentation conditions for the brewing of anti-hypertensive traditional rice wine comprised the addition of R. stolonifer No. 17 koji at a concentration of 35 sp/g and a fermentation period of 10 days at $25^{\circ}C$ using S. cerevisiae.

• Journal of Applied Biological Chemistry
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• 제49권4호
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• pp.125-130
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• 2006

In order to utilize non-commercial melon as alcoholic beverage material, in this study the optimum fermentation method and manufacture conditions were investigated and thereafter the properties of final product were determined. As for melon wine made with only melon juice, sensorial properties, particularly flavor, were not acceptable as alcoholic beverage. To improve the lack of melon wine, we made mash with cooked rice and Nuruk, and then added melon juice during fermentation. Acceptable sensorial properties were obtained in melon wine when 30% extract juice of oriental melon was added after 4 day of fermentation. The alcoholic beverage added melon juice showed much higher yellowness value than that without melon juice indicating that a clear yellow color similar to melon was actually observed in final product. Adding melon juice led little changes in amount and composition of free sugars, organic acids and amino acids and could improve sensorial properties.

• Journal of Microbiology and Biotechnology
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• 제19권10호
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• pp.1161-1168
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• 2009

Ethanol production by the simultaneous saccharification and fermentation (SSF) of low-value rice wine cake (RWC) without cooking was investigated. RWC is the filtered solid waste of fermented rice wine mash and contains 53% raw starch. For the SSF, the RWC slurry was mixed with the raw-starch-digesting enzyme of Rhizopus sp. and yeast, where the yeast strain was selected from 300 strains and identified as Saccharomyces cerevisiae KV25. The highest efficiency (94%) of ethanol production was achieved when the uncooked RWC slurry contained 23.03% starch. The optimal SSF conditions were determined as 1.125 units of the raw-starch-digesting enzyme per gram of RWC, a fermentation temperature of $30^{\circ}C$, slurry pH of 4.5, 36-h-old seeding culture, initial yeast cell number of $2{\times}10^7$ per ml of slurry, 17 mM of urea as the nitrogen additive, 0.25 mM of $Cu^{2+}$ as the metal ion additive, and a fermentation time of 90 h. Under these optimal conditions, the ethanol production resulting from the SSF of the uncooked RWC slurry was improved to 16.8% (v/v) from 15.1% (v/v) of pre-optimization.

• 한국식품과학회지
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• 제36권4호
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• pp.616-623
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• 2004

쌀과 포도의 혼합방법과 첨가방법을 달리하여 담금하였을 시 발효 중에 일어나는 이화학적인 특성과 관능검사 등을 통하여 얻어진 곁과는 다음과 같다. 쌀과 포도의 혼합비율을 달리하여 쌀포도주를 담금하였을 시, 알코올 농도는 쌀의 혼합비율이 높은 시험구 순서대로 높았으며, 최종 알코올 농도는 쌀의 혼합비율이 높은 시험구4, 시험구3, 시험구2 및 시험구1 순으로 18.4, 16.0, 14.9 및 12.9% 이였다. 발효종료후 pH는 pH 3.4-3.92이였고, 총산은 쌀의 혼합비율이 높은 시험구 순서대로 낮았다. 색도의 경우, 쌀 혼합비율이 높은 시험구 순서대로 L 값이 높았고, 반면에 a 값은 낮았다. 이상의 결과를 종합하면, 시험구 1, 즉 쌀과 포도의 혼합비율을 1 대 5로 하는 것이 쌀포도주를 담금하는 가장 적절한 방법으로 판단되었다. 쌀과 포도의 첨가방법을 달리하여 쌀포도주를 담금하였을 시, 3개 시험구의 알코올 농도는 대조구인 시험구1에 비해서 2.3-3.2% 낮았고, 발효종료 후 전 시험구의 총산은 0.72-0.74%로서 큰 차이가 없었다. 색도 면에서는 대조구인 시험구1은 a 값이 23.96이였으나, 시험구6, 시험구7 및 시험구8 순으로 23.76, 20.54 및 15.17 값을 나타내었다. 이상의 결과를 종합해 보면, 대조구와 같이 쌀을 먼저 발효시키고 2단 담금으로 포도를 발효시키는 것이 가장 효과적 방법으로 판단되었다. 관능검사 결과, 색과 향에서는 포도주를 더 선호한 반면, 맛에서는 쌀포도주를 더 선호하였으며, 종합적 기호도에서는 비슷하였다.

• 한국미생물·생명공학회지
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• 제37권4호
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• pp.413-415
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• 2009

To develop a new traditional rice wine by using Gardenia jasminoides, various fermentation methods such as without cooking, with cooking and with starter seed methods were studied. The condition of alcohol fermentation was investigated by addition of 1% Gardenia jasminoides into mash. Among the fermented methods, the fermentation with starter seed was the best as the alcohol was 19%. The acceptability of the Gardenia jasminoides rice wine with different methods were compared. The starter seed method which was prepared by adding 1% Gardenia jasminoides into mash showed the best acceptability in the sensory evaluation test and color test.

• 한국미생물·생명공학회지
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• 제30권4호
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• pp.410-414
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• 2002

아카시아꽃을 이용한 고부가가치의 생리기능성 전통주를 개발하기 위하여 먼저 아카시아 전통주의 알콜발효 조건을 검토하였다. 10%의 아카시아꽃을 함유한 덧밥에 누룩을 15% 첨가하고 Saccharomyces cerevisiae를 이용하여 제조한 주모를 첨가한 후 $25^{\circ}C$에서 20일간 발효시켰을 때 에탄올이 가장 많이 생성되었다. 또한, 기호도와 색상은 아카시아꽃 15% 첨가하여 제조한 전통주가 가장 좋았고 ACE 저해활성과 tyrosinase 저해활성은 각각 80.3%와 94.2% 이었고 전자공여능(23.4%)과 아질산염 제거활성(21.5%)도 대조구보다 높았다.

• KSBB Journal
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• 제30권1호
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• pp.33-37
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• 2015

Recently, several health benefits of rice wine, makgeolli, were known due to the interest on the traditional Korean liquor and the researches on the rice wine are increasing. Organic acids produced during the process of rice wine fermentation play important roles in the taste and flavor. In this study, we have examined the optimal conditions for lactic acid production in rice koji as a carbon source. Skim milk was also used as a supplementary ingredient for the optimization of lactic acid fermentation. Bacterial growth of Lactobacillus sakei was monitored under this condition. The pH, acidity of the culture and the ethanol tolerance of this bacterium were also tested. Through these experiments, we were able to optimize the growth condition of lactic acid bacteria by the addition of skim milk. This was also able to affect the change of pH, acidity, sugar concentration and alcohol tolerance, which might contribute to the improvement of the quality of rice wine. The optimal condition for the growth was 2 days with 10% (w/v) of skim milk concentration. With these results, it was confirmed that rice koji was an effective carbon source for the growth of lactic acid bacteria.