• 한국식품조리과학회:학술대회논문집
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• 한국식품조리과학회 1993년도 춘계 학술심포지움
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• pp.149-159
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• 1993

The concept of Solid-State Fermentation is briefly explained in comparison to other fermentation principles, and several types of fermenters are presented. A recently developed "Swing Reactor" for SSF is shown. When inoculated on rice, the mould Monascus purpureus forms red pigments, Which can be used as food colors (Ang-kak, Red Rice). By Response Surface Methodology, serveral factors have been optimized for maximal red colour formation. Showing that presoaking time of rice, pH of soaking water, age of preculture and inoculum size were not of importance within the observed limits. For a fermentation time of 7 days, start humidity is optimal at 34% and temperature is optimal at 28.8 C. These results of small scale fermentation could be transferred to the Swing Reactor.

• 한국식물병리학회:학술대회논문집
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• 한국식물병리학회 2003년도 정기총회 및 추계학술발표회
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• pp.107.1-107
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• 2003

The fermentation process and subsequent processing determine the efficacy of a bioherbicide propagule. Large batches of biomass of the mycoherbicide agent for white clover, Sclerotium sp.(BWC98-105) was produced in simple liquid fermentator in 5 gallons vessels(Model No. 8087, Dabo Inc., Korea) with oxygen supply(DPH16000, FineTech Inc., Korea) simulating industrial conditions by utilizing commercially available, inexpensive ingredients (10 ％ rice bran), The maximum biomass yield of Sclerotium sp.(BWC98-105) was obtained after 5 days of air pumped incubation at room temperature condition(22-28$^{\circ}C$). By using this simple facility, it could get fragmented or proliferated greatly and attained maximum mycelia biomass. The biomass of mycoherbicide agent consisted of hyphae devoid of spores. Biomass mycelia of the fungus 99％ survival at room temperature after 2 me. A thorough understanding of the effects of fermentation and formulation on viability and virulence is required to guide these processes. After an economical yield level of bioherbicide propagule has been achieved in a fermentation process, formulation becomes a critical factor which influences product efficacy. Because the fermentation must be stopped at a point when virulence/viability are optimum, the live bioherbicide propagule must be stabilized, formulated, and packaged.

• Journal of Microbiology and Biotechnology
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• 제16권12호
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• pp.1849-1855
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• 2006

It has been shown that the initial conditions of bacterial cultivation are extremely important for the successful production of hyaluronic acid (HA) by fermentation. We investigated several parameters that affect cell growth rate and the productivity and molecular weight of hyaluronic acid--i.e., agitation speed, aeration rate, culture temperature, pH, and pressure--to determine how to optimize the production of HA by Streptococcus zooepidemicus on an industrial scale. Using a 30-1 jar fermentor under laboratory conditions, we achieved maximum HA productivity and biomass when the agitation speed and aeration rate were increased simultaneously. By shifting the temperature downward from 35$^{\circ}C$ to 32$^{\circ}C$ at key levels of cell growth during the fermentation process, we were able to obtain HA with a molecular weight of $2.8{\times}10^6$ at a productivity of 5.3 g/l. Moreover, we reproduced these optimized conditions successfully in three 30-1 jar fermentors. By reproducing these conditions in a 3-$m^3$ fermentor, we were able to produce HA with a molecular weight of $2.9{\times}10^6$ at a productivity of 5.4 g/l under large-scale conditions.

• Journal of Microbiology and Biotechnology
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• 제23권9호
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• pp.1253-1259
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• 2013

The influences of glucose concentration, initial medium acidity (pH), and temperature on the growth and ethanol production of Saccharomyces cerevisiae NK28, which was isolated from kiwi fruit, were examined in shake flask cultures. The optimal glucose concentration, initial medium pH, and temperature for ethanol production were 200 g/l, pH 6.0, and $35^{\circ}C$, respectively. Under this growth condition, S. cerevisiae NK28 produced $98.9{\pm}5.67$ g/l ethanol in 24 h with a volumetric ethanol production rate of $4.12{\pm}0.24g/l{\cdot}h$. S. cerevisiae NK28 was more tolerant to heat and ethanol than laboratory strain S. cerevisiae BY4742, and its tolerance to ethanol and fermentation inhibitors was comparable to that of an ethanologen, S. cerevisiae D5A.

• 펄프종이기술
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• 제44권3호
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• pp.9-14
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• 2012

Formed fermentation inhibitors during acid saccharification leads to poor alcohol production based on lignocellulosic bio-alcohol production process. In this work, it is focused on the formation of fermentation inhibitors from xylan, which is influenced by reaction tempearature and time of acidic sacharifiaction of xylose and glucuronic acid. In second step of concentrated acid hydrolysis, part of xylose and glucuronic acid was converted to furfuraldehyde and formic acid by dehydration and rearrangement reactions. Furfural was form from xylose, which was highly sensitive to reaction temperature. Formic acid was come from both xylose and glucuronic acid, which supposed to main inhibitor in biobutanol fermentation. Reaction temperature of second hydrolysis was main variables to control the furfural and formic acid generation. Careful control of acid saccharification can reduce generation of harmful inhibitors, especially second step of concentrated sulfuric acid hydrolysis process.

• Journal of Microbiology and Biotechnology
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• 제23권4호
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• pp.489-498
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• 2013

A new Bacillus strain degrading starch, named Bacillus sp. UEB-S, was isolated from a southern Tunisian area. Amylase production using solid-state fermentation on millet, an inexpensive and available agro-resource, was investigated. Response surface methodology was applied to establish the relationship between enzyme production and four variables: inoculum size, moisture-to-millet ratio, temperature, and fermentation duration. The maximum enzyme activity recovered was 680 U/g of dry substrate when using $1.38{\times}10^9$ CFU/g as inoculation level, 5.6:1 (ml/g) as moisture ratio (86%), for 4 days of cultivation at $37^{\circ}C$, which was in perfect agreement with the predicted model value. Amylase was purified by Q-Sepharose anion-exchange and Sephacryl S-200 gel filtration chromatography with a 14-fold increase in specific activity. Its molecular mass was estimated at 130 kDa. The enzyme showed maximal activity at pH 5 and $70^{\circ}C$, and efficiently hydrolyzed starch to yield glucose and maltose as end products. The enzyme proved its efficiency for digesting raw cereal below gelatinization temperature and, hence, its potentiality to be used in industrial processes.

• 한국식품저장유통학회지
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• 제19권1호
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• pp.144-152
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• 2012

무증자 개량누룩 추출물을 흡착처리한 쌀을 이용한 막걸리의 온도변화와 품질특성을 분석 하였다. 술덧 발효 기간 중 대조구에 비해 누룩물처리쌀에서 전반적으로 낮은 품온을 유지하였고, 술덧발효 5일차부터 상승하는 양상을 보였다. 처리구 모두 효모, 젖산균, 초산균의 colony 수는 발효 초기 증가하다가 2일 이후부터 점차 감소하였다. pH는 발효 초기 낮았으나 발효가 진행됨에 따라 발효 3일차부터 상승하기 시작 하여 최종적으로는 초기보다 높은 양상을 보였다. 총산함량은 발효 1일차까지 급격히 증가하다가 그 이후에는 변화가 미미하였다. 전체적으로, 아미노산도와 가용성 고형분은 발효가 진행됨에 따라 증가 하였으며, 환원당은 발효 초기 낮아지다가 1일차부터 증가하였다. 알코올 함량은 대조구는 1일차에 6.87%로 시작하여 점차 증가하였으며, 이에 비해 누룩물처리쌀의 경우 1일차부터 9~11%로 높은 알코올 함량을 보이며 점차 증가하다가 발효 5일차이후에는 알코올 발효가 종료되었다. 최종 발효 후 술덧 내 유기산은 lactic acid가 주를 이루었다. 기호도평가에서는 24, 48, 72시간 누룩물처리쌀이 다른 처리구에 비해 맛과 전반적인 기호도에 있어서 우수한 평가를 받았다.

• Asian-Australasian Journal of Animal Sciences
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• 제27권6호
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• pp.832-840
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• 2014

This study aimed to investigate the effects of storage duration and temperature on the characteristics of wet brewers grains (WBG) as feeds for ruminant animals. Four storage temperatures ($5^{\circ}C$, $15^{\circ}C$, $25^{\circ}C$, and $35^{\circ}C$) and four durations (0, 1, 2, and 3 d) were arranged in a $4{\times}4$ factorial design. Surface spoilage, chemical composition and microorganism density were analyzed. An in vitro gas test was also conducted to determine the pH, ammonia-nitrogen and volatile fatty acid (VFA) concentrations after 24 h incubation. Surface spoilage was apparent at higher temperatures such as $25^{\circ}C$ and $35^{\circ}C$. Nutrients contents decreased concomitantly with prolonged storage times (p<0.01) and increasing temperatures (p<0.01). The amount of yeast and mold increased (p<0.05) with increasing storage times and temperatures. As storage temperature increased, gas production, in vitro disappearance of organic matter, pH, ammonia nitrogen and total VFA from the WBG in the rumen decreased (p<0.01). Our results indicate that lower storage temperature promotes longer beneficial use period. However, when storage temperature exceeds $35^{\circ}C$, WBG should be used within a day to prevent impairment of rumen fermentation in the subtropics such as Southeast China, where the temperature is typically above $35^{\circ}C$ during summer.

• 한국식품조리과학회지
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• 제13권5호
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• pp.578-584
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• 1997

저염 동치미 쥬스의 제조를 위하여 동치미의 발효 온도와 담금액의 소금농도가 동치미 쥬스의 물리화학적 특성 및 관능적 특성에 미치는 영향을 비교하여 최적 발효온도와 소금농도를 선정하고자 하였다. 동치미 담금은 무를 담금액(0.3~3.0% NaCl)과의 비율이 1:1(w/v)되게 용기에 담그고 파, 마늘, 생강을 첨가한 다음 10, 20, 3$0^{\circ}C$에서 발효하였다. 동치미의 발효속도는 온도가 높을수록 빠르게 진행되었고 소금농도의 영향은 발효온도에 따라 달랐다. 10. 2$0^{\circ}C$에서는 3.0%의 소금농도로 담근 동치미가 가장 빨리 pH 3.8에 도달하였으며 0.5%가 그 다음이었다. 그러나 3$0^{\circ}C$에서는 소금농도가 높을수록 발효속도가 느렸다. pH 3.9의 동치미 쥬스를 채점법으로 관능검사 한 결과 새콤한 내와 맛은 0.5%의 소금농도로 2$0^{\circ}C$에서 발효시킨 동치미 쥬스가 가장 높게 평가받았고 기호도 검사에서도 2$0^{\circ}C$에서 0.5% NaCl 담금액에 발효시킨 pH 3.8~4.0의 동치미 쥬스가 가장 좋은 결과를 보여주었다. 한편 2$0^{\circ}C$에서의 0.5% NaCl 보다 낮은 담금액에서는 발효가 빠르게 진행되었고 높은 탁도를 보여주었지만 0.5%의 소금농도로 담근 동치미 쥬스의 향미가 가장 적합한 것으로 나타났다.

• 농업과학연구
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• 제11권1호
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• pp.25-33
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• 1984

This experiment carried out to obtain the thermophilic yeast, suitable for ethanol fermentation, and two usable strain were isolated. And microbial characteristics of these strains were investigated, and ethanol fermentation tested. The results obtained were as follows; 1. The selected yeasts were identified D-71 with Saccharomyces cerevisiae, and J-515 with Saccharomyces fermentati. 2. The strains D-71 and J-515 were showed the highest ethanol fermentation activity in the crushed corn mash of high concentration at $35^{\circ}C$, and showed the slightly lower at $40^{\circ}C$ than in the case of $35^{\circ}C$. 3. The strains D-71 and J-515 were showed the very higher ethanol fermentation activity than that of compared strain at $35^{\circ}C$ and $40^{\circ}C$, and at these temperature, fermentation period was a little bit of short. 4. On fermentation test using D-71 and J-515, the residual total sugar in the mash was very lower at $35^{\circ}C$.