• 동아시아식생활학회지
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• 제4권1호
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• pp.19-29
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• 1994

In this paper a review of literature on Nuruk(yeast) between 1907 and 1945 was made, which showed that barley, rice bran, oat, rye, and other ingredients were originally used according to region and production quantity. Yeast can be classified into rough (Chokuk) and powder (Bunkuk) types depending on the degree of grinding. Yeast also had seasonal names, being called " Choonkuk", Hakuk", Jeolkuk", and "Dongkuk" in the spring, summer, autumn and wither respectively. The form of yeast in terms of quantity, size, and shape varied greatly by region, Production facilities were composed of plant structures to suit each process, enabling continuous output. The production process included shaping, placement in the fermenting chamber, piling by turns, risk-sifting and final output. Testing procudures were divided into visual inspection, physical testing, and chemical analyses.

• 한국산학기술학회논문지
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• 제14권8호
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• pp.3887-3896
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• 2013

본 연구의 목적은 쌀을 원료로 하여 증류주 제조시 쌀 특성에 적합한 최적의 증류주 효모를 선발하는데 있다. 사용된 5종류의 효모는 전반적으로 정상적인 발효패턴을 보였으나 송천효모(Y1)와 증류주 효모(Y5)가 다른 효모에 비해 우수한 발효력을 보였다. 또한 발효후 술덧을 분석한 결과 고급알코올은 증류주 효모(Y4, Y5)에서, 에스터는 송천효모(Y1)와 증류주효모(Y4, Y5)에서 유의적으로 높게 검출된 반면, 유기산 함량은 증류주 효모(Y3, Y4, Y5)에서 유의적으로 높게 나타났다. 발효술덧을 동증류기를 이용한 상압증류한 증류주 분석 결과 송천효모(Y1)와 증류주 효모(Y5)가 최종 알코올 농도가 높아 제조수율에 유리한 것으로 판단되며, 고급알코올과 에스터 등 향기 성분은 발효술덧 분석 결과와 같이 고급알코올은 증류주 효모(Y4, Y5)에서, 에스터는 송천효모(Y1)와 증류주 효모(Y4, Y5)에서 유의적으로 높게 나타나 발효술덧의 향기 패턴이 증류주에 대부분 전이되는 것으로 판단된다. 효모별 발효특성과 발효술덧 및 증류주의 물리화학적 특성, 관능평가를 종합한 결과 증류주 효모인 siha aktivehefe 6 brennereihefe(Y5)가 쌀을 이용한 증류주 품질 최적화에 가장 적합한 효모로 선발되었다.

• Mycobiology
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• 제42권4호
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• pp.346-352
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• 2014

Recently, the Q biotype of tobacco whitefly has been recognized as the most hazardous strain of Bemisia tabaci worldwide, because of its increased resistance to some insecticide groups. As an alternative control agent, we selected an Isaria javanica isolate as a candidate for the development of a mycopesticide against the Q biotype of sweet potato whitefly. To select optimal mass production media for solid-state fermentation, we compared the production yield and virulence of conidia between 2 substrates (barley and brown rice), and we also compared the effects of various additives on conidia production and virulence. Barley was a better substrate for conidia production, producing $3.43{\times}10^{10}$ conidia/g, compared with $3.05{\times}10^{10}$ conidia/g for brown rice. The addition of 2% $CaCO_3+2%$ $CaSO_4$ to barley significantly increased conidia production. Addition of yeast extract, casein, or gluten also improved conidia production on barley. Gluten addition (3% and 1.32%) to brown rice improved conidia production by 14 and 6 times, respectively, relative to brown rice without additives. Conidia cultivated on barley produced a mortality rate of 62% in the sweet potato whitefly after 4-day treatment, compared with 53% for conidia cultivated on brown rice. The amendment of solid substrate cultivation with additives changed the virulence of the conidia produced; the median lethal time ($LT_{50}$) was shorter for conidia produced on barley and brown rice with added yeast extract (1.32% and 3%, respectively), $KNO_3$ (0.6% and 1%), or gluten (1.32% and 3%) compared with conidia produced on substrates without additives.

• Journal of Microbiology and Biotechnology
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• 제27권2호
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• pp.226-233
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• 2017

Jeung-pyun, a fermented rice cake, is prepared by fermenting rice sourdough using makgeolli, a traditional Korean rice wine, in the presence of yeast and lactic acid bacteria (LAB). The goal of this study was to conduct biochemical and microbial analyses of five different rice sourdoughs, each fermented with a different commercial makgeolli, using culture-dependent and culture-independent approaches. All sourdough samples fermented with different makgeolli for 6.5 h showed different profiles in pH, total titratable acidity, organic acid concentration, and microbial growth. LAB belonging to different genera were identified based on colony morphology on modified MRS and sourdough bacteria agar medium. PCR-denaturing gradient gel electrophoresis analyses of the five sourdoughs showed different bands corresponding to LAB and yeast. 16S/26S rRNA gene sequence analyses of the samples confirmed that the predominant LAB in the five fermented rice doughs was Lactobacillus plantarum, Lb. pentosus, and Lb. brevis. Various other Lactobacillus spp. and Saccharomyces cerevisiae were common in all five fermented samples. This study provides comprehensive and comparative information on the microflora involved in fermentation of rice sourdough and signifies the need to develop effective starters to enrich the quality of jeung-pyun.

• 식품산업과 영양
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• 제14권2호
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• pp.25-32
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• 2009

• 한국산학기술학회논문지
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• 제19권9호
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• pp.206-214
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• 2018

본 연구는 2017년 8월부터 2018년 5월까지 수행되었으며 쌀맥주에 적합한 쌀의 첨가비율과 담금공정 및 맥주 타입을 선정하기 위한 기초자료를 확보하고자 쌀 첨가 비율 및 맥주 타입을 달리하여 맥주를 제조하고 품질특성을 비교 분석하였다. 쌀과 맥아의 비율을 0:100(S0), 20:80(S1), 40:60(S2), 60:40(S3), 80:20(S4)로 구분하여 액화, 당화 등 담금 공정상의 특성을 확인하였으며, 담금 시 승온방식과 자비방식에 대한 특성 비교와, 맥주 타입별(라거, 에일, 밀맥주)로 효모(하면 및 상면효모)를 달리 사용하여 특성을 연구하였다. 담금 시 특성을 파악한 결과, 쌀 첨가비율을 달리하여도 정상적인 담금시간을 보였으며 요오드 테스트도 정상으로 확인되었고, 1차 맥즙의 당도가 $21.0{\sim}21.6^{\circ}Brix$로 정상적인 당화가 이루어졌다. 담금방식은 3단 자비 방식에서 맥즙의 농도, 색도 및 향미가 가장 높게 나타났다. 맥주의 발효기간 중 당도, pH, 효모 수는 쌀과 맥아의 비율이나 효모 종류에 따른 차이가 크지 않았으며 발효도는 정상적인 범주에 든 것으로 나타났다. 고급알코올과 에스터 역시 쌀과 맥아의 비율과는 큰 상관이 없으며 밀맥주가 다소 높은 것으로 나타났다. 쌀 비율이 높을수록 색도(EBC)는 현저히 감소하였고, 고미가(BU)도 감소하였으며 기호도가 낮아졌다. 특히 쌀비율이 맥아비율보다 높을 때 기호도는 많이 떨어졌다. 본 연구의 결과를 기초로 쌀비율을 맥아비율보다 적게 하고 자비방식을 이용하여 맥즙의 향미를 증진시키고, 추후 맥주 타입별로 특수맥아의 활용과 다양한 홉을 사용하여 향미를 보완한다면 고품질의 경쟁력 있는 쌀맥주를 제조하는데 도움이 될 수 있으리라 판단된다.

• 한국식품저장유통학회지
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• 제2권2호
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• pp.269-276
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• 1995

Uncooked rice Tackju was prepared from the groud rice with different particle size such as 12, 20, 35 and 50 mesh, and its characteristics were analysed during the brewing. Reducing sugar and ethanol contents as well as yeast cell counts were the highest in main mash and Tackju prepared from 20 mesh fraction. Especially, reducing sugar content was about. 1.5-2.5 times as much as that obtained from 35 or 50 mesh fraction. The final concentration of ethanol in main mash prepared from 20 mesh fraction was 14.8%(v/v). It was about 1.5%(v/v) higher than the lowest one [13.35%(v/v)] which was prepared from 12 mesh fraction. No significant difference In total acidity was observed. Sensory evaluation revealed 20 or 35 mesh Tackju to be the best in overall preference, especially in sweet and refreshing tastes.

• 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.

• 한국식품영양학회지
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• 제11권4호
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• pp.381-387
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• 1998

The effects of culture conditions on the production of amylase expressed by Bacillus subtilis LKS88 with a cloned gene from Streptomyces albus KSM-35 were investigated. The production of amylase was increased significantly by using sodium citrate and rice hull as a carbon source. In addition, the use of a mixture of sodium citrate and rice hull (1:1) resulted in increase of enzyme production by 20-fold when compared to that of soluble starch. The soybean meal as the nitrogen source could be partially replaced with yeast extract without changing the enzyme production yield. The amylase production was also increased by adjusting initial pH to 6.0 or by adding 0.01% SDS. Maximum amylase production was observed in the medium containing 1.5% sodium cirtate, 1.5% rice hull, 0.7% soybean meal, 0.3% yeast extract, 0.66% K2HPO4, 0.05% MgSO4$.$7H2O, 0.008% CaCl2$.$2H2O, 0.01% SDS with initial pH of 6.0. The maximum yield of amylase reached 56.6 U/ml when B. subtilits LKS88 (pASA 240) was cultured at 37$^{\circ}C$ for 36 hr.

• Current Research on Agriculture and Life Sciences
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• 제29권
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• pp.37-42
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• 2011

본 연구에서는 효모에서 과 발현하는 Bax inhibior와 관련된 유전자를 동정하여 특성화 하였다. Yeast functional screening이라는 방법을 이용하여, 일반적은 환경에서 재배된 벼의 cDNA를 QX95001에 형질전 환하여 SD-galactose-Leu--Ura-배지에서 생성된 8개의 클론을 선발하였다. 그 중 AtBI-1과 같은 domain이 있는 D2-234를 포함하여 5개의 클론을 선발하였다. D2-243는 741bp의 염기서열과 247개의 아미노산으로 구성되었고 5 membrane-spanning 단편으로 되어 있음을 확인하였다. D2-234는 SD-galactose-$Leu^-$-$Ura^-$배지에서 세포성장이 왕성하였다. 본 실험에서 얻어진 결과는 벼 식물에서 나타나는 세포예정사와 관련된 단백질을 선발하는데 유용하게 이용될 것으로 생각된다.