• 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.

• Mycobiology
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• 제47권2호
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• pp.250-255
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• 2019

In the present study, we aimed to determine the cause of surface film formation in three rice vinegars fermented using the traditional static fermentation method. The pH and total acidity of vinegar were 3.0-3.3 and 3.0-8.7%, respectively, and acetic acid was the predominant organic acid present. Colonies showing a clear halo on GYC medium were isolated from the surface film of all vinegars. Via 16S rDNA sequencing, all of the isolates were identified as Acetobacter pasteurianus. Furthermore, field-emission scanning electron microscopy analysis showed that the bacterial cells had a rough surface, were rod-shaped, and were ${\sim}1{\times}2{\mu}m$ in size. Interestingly, cells of the isolate from one of the vinegars were surrounded with an extremely fine threadlike structure. Thus, our results suggest that formation of the surface film in rice vinegar was attributable not to external contamination, to the production of bacterial cellulose by A. pasteurianus to withstand the high concentrations of acetic acid generated during fermentation. However, because of the formation of a surface film in vinegar is undesirable from an industrial perspective, further studies should focus on devising a modified fermentation process to prevent surface film formation and consequent quality degradation.

• 한국식품조리과학회지
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• 제30권6호
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• pp.792-799
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• 2014

This study was conducted to determine the optimal conditions of acetic acid fermentation of aronia using the response surface methodology (RSM). Alcohol content of aronia wine was 13.1% after alcohol fermentation of aronia fruits. The optimal conditions of acetic acid fermentation were determined by five levels of initial aronia alcohol content, initial acetic acid content, and acetic acid bacteria, using the central composite design. The acetic acid yields, residual alcohol contents, pH, and color values (L, a, b) of acetic acid fermentation products were very significantly different ($p{\leq}0.01$), and were 26.34~57.82 g/L, 0.80~1.53%, 3.19~3.43, 47.58~71.00, 31.77~51.15, and 18.45~48.57, respectively. For the results, the optimal conditions of acetic acid fermentation of aronia were 7.78% of the initial alcohol concentration, 1.58% of the initial acetic acid, and 19.39% of the acetic acid bacteria.

• 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.

• 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.

• Journal of Microbiology and Biotechnology
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• 제22권7호
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• pp.975-980
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• 2012

Monacolin K-enriched ganghwayakssuk (Artemisia princeps Pamp.) was developed by fermentation with Monascus sp. Among the 15 Monascus spp. isolated previously from Monascus fermentation products, Monascus pilosus KMU108 produced 2,219 mg/kg of monacolin K during ganghwayakssuk fermentation with no detectable citrinin. The optimum concentrations of ganghwayakssuk and glucose determined from the response surface methodology (RSM) design were 2.2% and 3.8%, respectively. By applying these conditions, the monacolin K productivity was increased to 3,007 mg/kg after 15 days of fermentation. On the other hand, other characteristics such as the total content of flavonoids and phenolic compounds, and the antioxidant activity were relatively unchanged. Therefore, Monascus-fermented ganghwayakssuk is an excellent biomaterial for the development of functional foods because of its high level of monacolin K, known to lower cholesterol levels.

• 한국식품영양과학회지
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• 제30권3호
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• pp.460-465
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• 2001

농축사과주스의 효율적 활용을 위하여 반응표면분석으로 사과식초 발효조건을 알콜발효 및 초산발효 2단계로 구분하여 최적화 및 모니터링하였다. 알콜발효에서 최대 알콜함량을 나타내는 조건은 초기당도 $18.56\;^{\circ}Brix$, 교반속도 61.99 rpm 및 발효시간 67.32 hr으로 나타났으며, 초산발효에서 총산이 최대치를 나타내는 조건은 교반속도 201.53 rpm, 발효시간 179.42 hr으로 나타났다. 예측된 알콜발효 및 초산발효 최적 조건으로 발효를 행한 결과 총산 7.8%의 사고식초를 생산할 수 있었다. 알콜발효 과정에서 malic acid 함량이 가장 높았으며, 시간이 경과됨에 따라 lactic acid가 증가하였다. 초산발효 과정에서는 acetic acid가 급격히 증가하였으며, malic acid 함량은 거의 변화가 없었다.

• 한국식품영양과학회지
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• 제32권4호
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• pp.539-543
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• 2003

매실을 사용하여 알콜을 생산하기 위하여 당농도, 발효온도, 발효시간의 3변수와 5수준의 fractional factorial design으로 RSM computer program을 사용하여 최적 발효조건을 조사하였다 알콜함량에 대한 회귀분석결과, $R^2$는 0.9276으로 높게 나타났다. 당농도 8.39%, 발효온도 28.86$^{\circ}C$에서 3.84일간 발효하는 것이 알코올 생성을 위하여 가장 양호하였으며, 이 조건에서의 알코올 생성 예상치는 5.24%이었다.

• 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.

• Journal of Microbiology and Biotechnology
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• 제1권2호
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• pp.130-135
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• 1991

The effects of media composition on citric acid fermentation using surface immobilized Saccharomycopsis lipolytica were studied. The use of the standard medium for these organisms resulted in rapid decrease of citric acid production and a transformation of immobilized cell morphologies from a yeast-type to a mycelium-type. When the standard medium was enriched with vitamins, trace minerals, a growth factor and ammonium to form a Vigorous Stationary Phase (VSP) fermentation type medium, relatively stable citric acid production (10 mg/lㆍh) was obtained. Using the VSP type medium, the surface immobilized cells also retained their yeast-type form.