• 동아시아식생활학회지
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• 제8권1호
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• pp.57-65
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• 1998

To utilize deteriorated sweet persimmon effectively, response surface methodology(RSM) was used to determine the optimal vinegar fermentation conditions and monitored by a divided two stage fermentation. The optimum conditions for maximum alcohol content were obtained when the first stage (alcohol fermentation) was carried out with an initial sugar concentration of 18.5$^{\circ}$Brix, agitation rate of 140.8 rpm, fermentation time of 127.6 hr. When sugar concentration was 14$^{\circ}$Brix maximum alcohol content(7.1%) was predicted at fermentation conditions of 160 rpm in agitation rate, 140hr in fermentation time. The optimum conditions for maximum acidity were obtaiend when second stage(vinegar fermentation)was carried out 249.5 rpm in agitation rate, 148.8 hr in fermentation time. Predicted values at the optimum conditions were similar to experimental values.

• 한국미생물·생명공학회지
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• 제22권5호
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• pp.531-537
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• 1994

This study was undertaken with objective of optimizing the conditions of fermentation in an aqueous two-phase system which is composed of polyethylene glycol (PEG) 20000 and crude dextran (Dx). The data were obtained and analyzed using the Box-Wilson's experimental design protocol and the response surface methodology. To reach this end a multilinear polynomial regres- sion model was developed, which can be utilized for the purpose of optimizing the extractive fermentation. Optimum conditions for batch fermentation with aqueous two phase system were found to be at 4.2~5.4% PEG/3.2~4.2% Dx range. The composition of the center was 4.8% PEG/ 3.6% Dx. Optimum operating conditions for initial sugar concentration and fermentation time were approximately 160 g/l, and 21~22 hr, respectively. Fermentation in the aqueous two phase system composed of 5% PEG/4% Dx showed increase of 23% in ethanol concentration, of 9.5% in ethanol yield, and of 19% in ethanol productivity as compared to the case of fermentation of neat Jerusalem artichoke juice.

• 한국식품저장유통학회지
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• 제30권6호
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• pp.905-917
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• 2023

The optimal fermentation conditions for producing fermented black soybeans rich in sulfur-containing amino acids were investigated. Response surface methodology monitored fermentation conditions. A central composite design examined the effect of independent variables: enzyme concentration (X₁) and fermentation time (X₂) on yield and methionine content. Both factors significantly influenced these dependent variables. Enzyme concentration more profoundly affected amino nitrogen content than fermentation time. β-Glucan content and cystine level were primarily affected by fermentation time. We elicited each variable's regression formula and identified optimal fermentation conditions for functional compounds. The predicted optimum conditions were an enzyme concentration of 0.28-0.32% and a fermentation time of 58.0-62.0 min. Under these optimal conditions, each black soybean variety's sulfur amino acid content ranged from 818.62 to 922.62 mg/100 g, demonstrating significant variety differences.

• Food Science and Biotechnology
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• 제18권5호
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• pp.1083-1090
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• 2009

Fermentation of wort was investigated with an ultimate goal to develop a fermented beverage rich in prebiotics and functional ingredients as well as desirable in flavors. Wort was fermented with Leuconostoc citreum HJ-P4 originated from kimchi and subjected to sensory descriptive analysis. L. citreum HJ-P4 produced various organic acids (e.g., lactic acid, acetic acid) as well as functional sugars (e.g., mannitol, panose) during wort fermentation. The concentration and ratio of lactic acid and acetic acid were significantly influenced by roasting conditions of malts used for wort preparation and aeration conditions during fermentation. The concentration of mannitol and panose varied depending on the sucrose content of wort and aeration conditions. Sensory characteristics of the fermented worts were clearly differentiated according to the roasting conditions of malts used for wort preparation and aeration conditions during fermentation. These results indicate that metabolite concentration of fermented wort and its sensory properties can be manipulated with roasting conditions of malts and fermentation conditions.

• Journal of Microbiology and Biotechnology
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• 제17권2호
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• pp.297-304
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• 2007

The effect of yeast propagated at different aeration conditions on yeast physiology, fermentation ability, and beer quality was investigated using three strains of Saccharomyces cerevisiae. It was shown that yeast cells grown under continuous aeration conditions during propagation were almost two times higher as compared with discontinuous aeration conditions. The maximum of cell growth of all samples reached between 36 hand 48 h. The concentration of trehalose was increased under continuous aerated yeasts, whereas glycogen was decreased. It was also observed that the concentration of glycogen and trehalose in yeast cells had no direct effect on subsequent fermentation ability. The effect of yeast propagated under different aeration conditions on subsequent fermentation ability was different from yeast strains, in which the influence will be most pronounced at the first fermentation. Later, the yeasts might regain its original characteristics in the following fermentations. Generally, continuously propagated yeast had a positive effect on beer quality in subsequent fermentation. Hence, the concentration of aroma compounds obtained with yeast propagated under 6 1/h for 48 h aeration was lower than those grown under other aeration conditions in the bottom yeasts; in particular, the amounts of phenylethyl alcohol, ester, and fatty acids were decreased.

• 한국환경과학회지
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• 제21권10호
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• pp.1255-1263
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• 2012

Batch cultivations were performed to evaluate the influences of the initial pH condition on mesophilic and thermophilic acidogenic fermentation with food waste recycling wastewater. In both conditions of mesophilic and thermophilic fermentation, TVFAs production rates were maximized at the initial pH 7 condition as 0.15 and 0.23 g TVFAs/L hr, respectively. And pH was also maintained stably between 6 and 7 during 72hr acidogenic cultivation at both conditions. However, predominant VFA components were different according to reaction temperature conditions. In mesophilic condition, propionic acid which has low conversion efficiency to methane was accumulated up to 1,348 mg/L while acetic and butyric acid were predominant in thermophilic condition. Therefore, thermophilic acidogenic fermentation was superior for the effective VFAs production than mesophilic condition. From the DGGE analysis, the band patterns were different according to the initial pH conditions but the correlations of the each band were increased in similar pH conditions. These results mean that microbial communities were certainly affected by the initial pH condition. Consequently, the adjustment of the initial pH to neutral region and thermophilic operation are needed to enhance acidogenic fermentation of food waste recycling wastewater.

• 한국식품영양과학회지
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• 제46권8호
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• pp.986-996
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• 2017

본 연구에서는 우엉을 이용한 식초의 제조 가능성을 검토하였으며, 반응표면분석법을 통하여 우엉식초의 발효조건에 대한 영향을 모니터링하여 발효조건을 최적화하였다. 그리고 제조된 우엉 발효식초의 기능성 성분과 유효성분을 확인하였다. 식초 제조를 위해 우엉 추출액에 사과 농축액을 15% 첨가하여 알코올 발효시킨 결과, 5일 후 6.4%의 알코올이 생성되었다. 초산 발효조건을 확립하기 위해 중심합성계획법에 따라 발효시간, 발효온도를 독립변수로 하여 실험을 계획하였고, 발효액의 특성을 반응변수로 하여 실험한 후 발효조건을 최적화하였다. 17일간의 초산 발효 후 13개 실험구의 acetic acid 함량은 3.85~4.73%였으며, $R^2$ 값은 0.9850으로 1% 이내 유의수준에서 유의성이 인정되었다. Arctiin 함량의 범위는 0.37~0.50 mg%였으며, $R^2$ 값은 0.8380으로 5% 이내 유의수준에서 유의성이 인정되었다. 각 변수에 대한 회귀식을 도출하여 우엉식초 제조를 위한 최적 발효조건을 superimposing 한 결과 발효시간은 16일, 발효온도는 $30^{\circ}C$로 예측되었다.

• 산업식품공학
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• 제15권4호
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• pp.355-361
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• 2011

고 함량 이소플라본 생산을 위한 대두의 침지, 발아조건 및 청국장 발효 최적조건을 찾기 위해 반응표면분석법을 사용하였다. 대두의 침지와 발아조건은 대두를 25.6$^{\circ}C$에서 7 hr 침지 후 29.1$^{\circ}C$에서 42.4 hr 발아 시 이소플라본 함량이 가장 높게 측정이 되었다. 또한 고함량 이소플라본을 얻기위한 청국장 발효 최적 조건은 온도 39.96$^{\circ}C$, 접종량 1.32%, 42.4 hr 이었다. 최적조건에서의 이소플라본 함량은 2,544 ppm으로 대조구(1,960 ppm)보다 약 1.3 배 향상되었다.

• 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.

• 한국응용과학기술학회지
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• 제40권4호
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• pp.699-709
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• 2023

This study is to establish optimizing condition of alcohol fermentation in vinegar production with aronia, to confirm whether this can be industrially used, and to compare and analyze a change in anti-oxidative activity and quality characteristic according to alcohol fermentation of aronia. The optimized conditions for alcohol fermentation were as follows: Saccharomyces cerevisiae 5645 of yeast strain, a 5% inoculum size, aronia juice with a brix value of 14, and a glucose content of 7%. As a result to conduct scale up with optimizing conditions of alcohol fermentation of aronia, 8 days (192 hrs) of total alcohol fermentation time and 7.4% of the final alcohol content. The harvest volume accounted for approximately 90.2% with a loss of about 2.8%. As a result of antioxidant test, anti-oxidative activity of alcohol fermented liquor is lower than anti-oxidative activity of aronia extract, because of the decrease of antioxidant by oxidation of the fermentation process. However, the decrease of tannin by the fermentation process reduces acerbity of aronia, so increases overall preference