• 한국식품과학회지
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• 제29권4호
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• pp.745-751
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• 1997

찹쌀로 담금한 재래식 고추장의 발효과정 중 휘발성 향기성분을 purge and trap 장치로 포집하여 GC-MSD로 분석, 동정하였다. 재래식 고추장에서 alcohol류 19종, ester류 13종, acid류 7종, aldehyde류 3종, alkane류 1종, ketone류 2종, amine 2종, benzene류 1종, alkene 1종, phenol류 1종, 기타 1종 등 51종의 향기성분이 동정되었고 동정된 향기성분은 담금 직후에 22종이었으나 30일에 41종으로 증가되었고 120일에는 51종으로 향기성분수가 가장 많았다. 이들 성분 중 숙성 전과정을 통하여 공통으로 검출된 성분은 acetic acid-ethyl ester, ethanol, butanoic acid-ethyl ester, 1-butanol, 2-methyl-1-propanol, 3-methyl-1-butanol, butanoic acid, ethenone등 22종이었다. 휘발성 향기성분의 면적비율은 담금 직후에 1-butanol이 30일 이후는 ethanol이 가장 높았다. 고추장 향기성분의 면적비율(peak area%)은 숙성기간에 따라 다소 차이가 있으나 acetic acid-ethyl ester, ethanol, butanoic acid-ethyl ester, 1-butanol, 3-methyl-1-butanol, 2-methyl-1-propanol 등이 높아 재래식고추장의 휘발성 향기성분의 주성분으로 추측된다.

• 한국식품영양학회지
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• 제20권2호
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• pp.195-201
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• 2007

This study were investigated the changes in chemical components, quality characteristics of the fermented broth, and physiological functionality during fermentation period of fruit, vegetables, and medicinal herbs. pH and $^{\circ}$Bx gradually decreased and the viscosity increased. The chromaticity of L, a, and b all increased. The total number of germs dropped from $10^5{\sim}10^6\;to\;10^2{\sim}10^3$ CFU/ml, and that of lactobacilli also decreased noticeably. According to the result of the effect on fat oxidation, a very low level of TBARS was shown. After thirty days of fermentation, the amount of each fermentation broth increased more or less, but as it declined considerably after ninety days, it was found that the binding effect of $Fe^{2+}$ ion was small and insignificant. The electron donating ability, though not reaching 0.5% ascorbic acid, showed a high level of activity from $33.71{\sim}72.15%$ before fifteen days and $44.76{\sim}75.20%$ ninety days after fermentation. Among them, the fruit fermentation solution showed the highest activity. It was also found that the organic functions for each fermentation broth decreased more or less depending on the fermentation period and the thirty-days-old fermentation broth were favored most. On the basis of the above experiment results, it can be concluded that the optimum fermentation period for fruit, vegetables, and medicinal herb is thirty to ninety days.

• 한국식품과학회지
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• 제30권5호
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• pp.1203-1208
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• 1998

떫은감의 이용성 증진과 품질이 우수한 감식초 발효조건을 최적화하였다. 품질이 일정하고 단기간에 대량생산이 가능한 발효조건을 확립하기 위하여 반응 표면분석으로 식초 제조조건을 알콜발효와 초산발효 2단계로 구분하여 모니터링하였다. 그 결과 1단계 알콜발효에서 알콜함량이 최대치를 나타내는 조건은 원료감의 당도 $20.51\;^{\circ}Brix$, 교반속도 139.52 rpm, 발효시간 94.88 hr으로 나타났다. 그러나 떫은감의 당도가 $14\;^{\circ}Brix$ 정도임을 감안하여 제한조건으로 초기당도를 $14\;^{\circ}Brix$로 정한 후 최적조건을 예측하여 본 결과 발효 시간 120 hr, 교반속도 40 rpm에서 알콜수율이 7.1%로 나타났다. 이와 같이 설정된 조건으로 알콜발효를 행한 후 2단계로 초산발효를 행하여 초산발효조건을 예측한 결과 총산이 최대치를 나타내는 조건은 교반 속도 224.40 rpm, 발효시간 176.07 hr로 나타났다. 최적조건에서 예측된 알콜발효 및 초산발효의 결과는 최적조건으로 실제 발효를 행한 결과와 유사하였다.

• 한국식품과학회지
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• 제35권2호
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• pp.272-279
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• 2003

산야채를 이용하여 추출물 발효식품을 제조하는데 있어서 적합한 발효기간을 설정하기 위하여 발효기간의 경과에 따른 발효액의 성분과 품질특성, 효소활성과 생리기능성의 변화를 조사하였다. 발효기간이 경과함에 따라 pH와 $^{\circ}Bx$는 점차 낮아졌으며, 점도는 감잎 추출물 발효액을 제외하고는 3개월 경과시 현저히 낮아졌다. 색도는 발효기간이 증가함에 다라 L값과 a값은 증가되고, b값은 감소되는 경향이었다. 발효액 중의 amylase 효소활성은 발효 6개월이 경과하면서 발효 전에 비하여 $167{\sim}800%$ 수준으로 증가하였고, invertase는 발효 초기에는 활성이 거의 없었으나 1개월 경과시에 $60{\sim}170$ units의 약한 활성을 나타내었으며, cellulase는 거의 활성을 나타내지 않았다. 총 페놀함량과 항산화활성도는 발효가 진행됨에 따라 증가하여 $3{\sim}4$개월시 가장 높았고, 그 이후에는 감소하는 경향이었다. Tyrosinase 저해활성은 쑥을 제외한 모든 발효액에서 활성을 나타내었으며, 발효기간에 따라 큰 변화가 없었다. SOD 유사활성은 아카시아와 감잎 발효액에서 각각 $23.1{\sim}25.1%,\;26.8{\sim}29.2%$의 약한 활성을 나타내었으며, 발효 기간에 따라 큰 변화가 없었다. 관능적인 특성을 조사하였을 때 쑥은 발효 기간에 따라 큰 차이가 없었고, 솔잎은 발효기간이 증가되면서 맛과 냄새의 강도가 높아졌으며, 전체적인 기호도가 발효 3개월에서 가장 좋은 것으로 평가되었다. 이상의 결과를 종합해 볼 때 산야채 추출물의 발효기간은 $3{\sim}4$개월 정도가 적합할 것으로 판단된다.

• Journal of Microbiology and Biotechnology
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• 제19권5호
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• pp.462-467
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• 2009

Cyclosporin A (CyA) produced by Tolypocladium inflatum is a promising drug owing to its immunosuppressive and antifungal activities. From an industrial point of view, the necessity to obtain a suitable and economic medium for higher production of CyA was the aim of this work. The present study evaluated the effect of different fermentation parameters in solid state fermentation, such as selection of solid substrate, hydrolysis of substrates, initial moisture content, supplementation of salts, additional carbon, and nitrogen sources, as well as the inoculum age and size, on production of CyA by Tolypocladium inflatum MTCC 557. The fermentation was carried out at $25{\pm}2^{\circ}C$ for 9 days. A combination of hydrolyzed wheat bran flour and coconut oil cake (1:1) at 70% initial moisture content supported a maximum production of $3,872{\pm}156\;mg$ CyA/kg substrate as compared with $792{\pm}33\;mg/kg$ substrate before optimization. Furthermore, supplementation of salts, glycerol (1% w/w), and ammonium sulfate (1% w/w) increased the production of CyA to $5,454{\pm}75\;mg/kg$ substrate. Inoculation of 5 g of solid substrate with 6 ml of 72-h-old seed culture resulted in a maximum production of $6,480{\pm}95\;mg$ CyA/kg substrate.

• Journal of Microbiology and Biotechnology
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• 제24권5호
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• pp.629-638
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• 2014

This study describes an alternative mixed culture fermentation technology to anaerobically convert lignocellulosic biomass into butyric acid, a valuable product with wide application, without supplementary cellulolytic enzymes. Rice straw was soaked in 1% NaOH solution to increase digestibility. Among the tested pretreatment conditions, soaking rice straw at $50^{\circ}C$ for 72 h removed ~66% of the lignin, but retained ~84% of the cellulose and ~71% of the hemicellulose. By using an undefined cellulose-degrading butyrate-producing microbial community as butyric acid producer in batch fermentation, about 6 g/l of butyric acid was produced from the pretreated rice straw, which accounted for ~76% of the total volatile fatty acids. In the repeated-batch operation, the butyric acid production declined batch by batch, which was most possibly caused by the shift of microbial community structure monitored by denaturing gradient gel electrophoresis. In this study, batch operation was observed to be more suitable for butyric acid production.

• Journal of Microbiology and Biotechnology
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• 제14권6호
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• pp.1163-1169
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• 2004

An unstructured mathematical model is presented for lactic acid fermentation based on the energy balance. The proposed model reflects the energy metabolic state and then predicts the cell growth, lactic acid production, and glucose consumption rates by relating the above rates with the energy metabolic rate. Fermentation experiments were conducted under various initial lactic acid concentrations of 0, 30, 50, 70, and 90 g/l. Also, a genetic algorithm was used for further optimization of the model parameters and included the operations of coding, initialization, hybridization, mutation, decoding, fitness calculation, selection, and reproduction exerted on individuals (or chromosomes) in a population. The simulation results showed a good fit between the model prediction and the experimental data. The genetic algorithm proved to be useful for model parameter optimization, suggesting wider applications in the field of biological engineering.

• Journal of Animal Science and Technology
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• 제60권6호
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• pp.15.1-15.10
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• 2018

Methane emission from the enteric fermentation of ruminant livestock is a main source of greenhouse gas (GHG) emission and a major concern for global warming. Methane emission is also associated with dietary energy lose; hence, reduce feed efficiency. Due to the negative environmental impacts, methane mitigation has come forward in last few decades. To date numerous efforts were made in order to reduce methane emission from ruminants. No table mitigation approaches are rumen manipulation, alteration of rumen fermentation, modification of rumen microbial biodiversity by different means and rarely by animal manipulations. However, a comprehensive exploration for a sustainable methane mitigation approach is still lacking. Dietary modification is directly linked to changes in the rumen fermentation pattern and types of end products. Studies showed that changing fermentation pattern is one of the most effective ways of methane abatement. Desirable dietary changes provide two fold benefits i.e. improve production and reduce GHG emissions. Therefore, the aim of this review is to discuss biology of methane emission from ruminants and its mitigation through dietary manipulation.

• 한국수소및신에너지학회논문집
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• 제26권3호
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• pp.247-259
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• 2015

This study was performed to investigate the application of dark $H_2$ fermentation to two-stage bioprocesses for organic waste treatment and energy production. We reviewed information about the two-stage bioprocesses combining dark $H_2$ fermentation with $CH_4$ fermentation, photo $H_2$ fermentation, microbial fuel cells (MFCs), or microbial electrolysis cells (MECs) by using academic information databases and university libraries. Dark fermentative bacteria use organic waste as the sole source of electrons and energy, converting it into $H_2$. The reactions related to dark $H_2$ fermentation are rapid and do not require sunlight, making them useful for treating organic waste. However, the degradation is not complete and organic acids remain. Thus, dark $H_2$ fermentation should be combined with a post-treatment process, such as $CH_4$ fermentation, photo $H_2$ fermentation, MFCs, or MECs. So far, dark $H_2$ fermentation followed by $CH_4$ fermentation is a promising two-stage bioprocess among them. However, if the problems of manufacturing expenses, operational cost, scale-up, and practical applications will be solved, the two-stage bioprocesses combining dark $H_2$ fermentation with photo $H_2$ fermentation, MFCs, or MECs have also infinite potential in organic waste treatment and energy production. This paper demonstrated the feasibility of two-stage bioprocesses combining dark $H_2$ fermentation as a novel system for organic waste treatment and energy production.

• 한국수산과학회지
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• 제27권2호
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• pp.121-126
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• 1994

감자 마쇄물을 이용하여 멸치젓갈의 숙성조절에 관하여 연구 검토 하였으며 그 결과를 요약하면 다음과 같다. 1. 감자 마쇄물 $8\%$(w/w) 첨가구(P)가 숙성 전 기간에 걸쳐 육과 액즙에서 아미노 질소 함량이 낮게 유지되었으며 육의 외관도 거의 변화없이 유지되어 숙성 억제효과가 우수한 것으로 나타났다. 2. 숙성초기 아미노 질소 함량이 낮게 유지되고 pH 및 생균수의 증식이 억제되는 것이 숙성억제와 관계가 있는 것으로 나타났다.