• 한국식품조리과학회지
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• 제6권2호
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• pp.1-6
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• 1990

The purpose of this study was to investigate the effects of preheating and salt concentration on the fermentation rate and firmness of cucumber kimchi, and the relationship between firmness and the contents of pectin fractions, hemicellulose and cellulose during fermentation. For this purpose, pH, acidity, firmness and the contents of pectic fractions, hemicellulose and cellulose were studied. 1. The changes of pH and titratable acidity indicated that preheating and high salt concentration delayed the fermentation rate in cucumber kimchi. 2. After 9 days, preheated cucumber kimchi was firmer than nonpreheated cucumber kimchi. 3. During fermentation, the cucumber kimchi fermented at 5% NaCl was firmer than that femented at 2% NaCl. 4. After 9 days, preheated cucumber kimchi was higher in insoluble pectin (HCISP)content and lower in soluble pectin (HWSP & HXSP) content than nonpreheated cucumberkimchi and hese results in accord with those of firmness measurements. 5. During fermentation, the cucumber kimchi fermented at 5% NaCl was higher in insoluble pectin content and lower in soluble pectin content than nonpreheated cucumber kimchi, and these results were in accord with those of firmness measurement. 6. During fermentation, cellulose content decreased.

• 한국식품영양학회지
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• 제30권4호
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• pp.788-795
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• 2017

This research has attempted to investigate the volatile flavor compounds of onion products through acetic fermentation, and to create a natural beverage with beneficial biological properties which can also fulfill customer quality standards. Onion products (OAF (M): Onion extracts at five days of acetic fermentation, OAF (F): Onion extracts at ten days of acetic fermentation) were produced by acetic fermentation. Volatile flavor compounds from onion extracts, OAF (M) and OAF (F) were used by Mixxor liquid extractions and analyzed by GC/MSD. Compounds of 49, 75 and 69 were identified in onion extracts, OAF(M) and OAF(F) respectively. Among the major volatile flavor compounds classes, sulfur containing compounds (36.7%), acids (31.2%) and aldehydes (13.5%) in onion extracts were changed into acids (69.6%) and alcohols (24.6%) in OAF (M) and acids (80.6%) and alcohols (15.5%) in OAF (F). During acetic fermentation acetic acid, 1,3-butanediol (odorless) and 2,3-butanediol (onion flavor) increased remarkably, sulfur-containing compound such as 2,5-dimethylthiophene having anti-oxidant activities was detected by fermentation.

• 한국미생물·생명공학회지
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• 제51권2호
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• pp.184-190
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• 2023

Bioethanol has recently attracted much attention as a sustainable and environmentally friendly alternative energy source. This study aimed to develop a potential process for bioethanol production by fed-batch fermentation using instant dry yeast. To obtain the highest cell growth, we studied the influence of the initial sugar concentrations and pH of sugarcane molasses in batch fermentation. The batch system employed three levels of sugar concentrations, viz. 10%, 15%, 20% (w/v), and two levels of pH, 5.0 and 5.5. The highest cell growth was achieved at 20% (w/v) and pH 5.5 of molasses. The fed-batch system was then performed using the best batch fermentation conditions, with a molasses concentration of 13% (w/v) which resulted in high ethanol concentration and fermentation efficiency of 15.96% and 89%, respectively.

• 한국식품과학회지
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• 제43권1호
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• pp.77-82
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• 2011

본 연구는 메밀 속성장의 품질 특성을 조사하고자 아미노태 질소, 총균수, B. cereus 개체수 변화, 향기성분, 혈전용해능, 항산화도, ACE 저해도 및 관능검사를 분석하였다. 그 결과, 아미노태 질소함량은 발효 중 점차 증가하였으며 발효 30일 경과 후, 메밀 60% 첨가 속성장은 258.2 mg%로 나타났다. 이는 메밀 60% 첨가 속성장의 총균수 8.2 log CFU/mL와 유사한 경향을 보였고, 메밀함량이 증가할수록 발효미생물 증식에 영향을 미치는 것을 확인하였다. 또한 발효 중 B. cereus의 개체수 변화를 확인하여 메밀 속성장의 가식기간을 발효 30일 이후로 결정하였다. 메밀 속성장의 향기성분은 acetaldehyde, butanol 및 pyrazine이 검출되었다. 메밀 속성장 10% 추출물의 혈전용해능은 120.8 unit로 대조구 71.6 unit에 비해 우수하였으며, 항산화력 또한 메밀 속성장 추출물이 동일 농도에서 높은 값을 나타냈다. 관능검사 결과, 메밀함량 50% 처리구에서 색, 맛, 향, 조직감 및 전반적인 기호도가 유의적(p<0.001)으로 우수한 결과를 보였다. 따라서, 본 연구결과는 위생적으로 안전하고, 생리활성 및 관능적으로 우수한 새로운 형태의 메밀 속성장을 30일 내에 제조됨을 제시한다.

• 한국식품과학회지
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• 제40권4호
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• pp.479-484
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• 2008

김치를 제조할 때 마늘이 김치의 발효를 촉진시킬 때도 있지만 영향을 미치지 못할 때도 있었다. 배추 자체만으로도 발효가 충분히 일어나는 가을 배추김치에는 마늘을 첨가하여도 발효촉진 작용이 나타나지 않았지만, 자체만으로는 발효력이 약한 봄 배추김치에는 마늘을 첨가했을 때 발효촉진 현상이 관찰되었다. 봄 배추를 사용하여 만든 김치에 포도당, yeast extract와 peptone, 김치 부재료를 각각 따로 첨가했을 때에도 마늘을 첨가했을 때와 같은 촉진현상이 관찰되었으나, 가을 배추김치에서는 촉진현상이 거의 나타나지 않았다. 따라서 마늘이 김치의 발효를 촉진하는 현상은 마늘 특유의 고유한 성분에 의한 촉진작용이 아니고 배추의 영양소 구성성분 특성에 따라 나타나는 현상으로 해석되었다. 즉, 마늘의 첨가를 통해 공급되는 당이나 영양성분이 봄 배추의 부족한 영양을 보충해 줌으로써 나타나는 일반적인 현상으로 판단되었다.

• 한국식생활문화학회지
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• 제26권2호
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• pp.178-183
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• 2011

The objective of this study was to determine the quality and sensory characteristics of ginpi wine using different levels of ginpi at each fermentation step. In the first mash with or without ginpi, lactic acid bacteria and yeast counts were maximum between days 2 and 3 of fermentation. The reducing sugar content increased after 2 days of fermentation of the first mash. Brix content increased rapidly after 1 day of fermentation, but pH decreased rapidly. After 3 days of fermentation of the second mash, 0, 30, 60, or 90 g of ginpi were added, and the yeast counts were 8.89, 8.72, 8.81, and 8.88 \log CFU/mL, respectively but then continually decreased. After 3 days of ginpi wine fermentation of the second mash, the addition of 0, 30, 60, 90 g ginpi resulted in alcohol content of 11.40, 8.90, 9.40, and 8.95%, respectively, and after 3 days of fermentation, alcohol content increased slightly. The results of a sensory evaluation showed that overall acceptability of ginpi wine was not different with different levels of added ginpi. However, the flavor of the 90 g ginpi wine had the highest acceptability.

• 동아시아식생활학회지
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• 제23권5호
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• pp.620-628
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• 2013

In this study, the condition for preventing abnormal fermentation was set by heating the nuruk extract, such that glycosyl enzymes maintain its activity and unnecessary microbes are removed. The total colony of microbes in the heated nuruk extract was highest in number at $25^{\circ}C$ and began to reduce at 50, $60^{\circ}C$ and sharply reduced over $70^{\circ}C$. Saccharogenic power (SP), glucoamylase and acidic protease activities were highest at $50^{\circ}C$, 10, 20, 30min and ${\alpha}$-amylase activity was lower at $50^{\circ}C$ than at $25^{\circ}C$. In the pHs of the nuruk extract, as the heat temperature became higher and treatment time was longer, the pHs were reduced significantly. The total acidities of heat treatments at 50, $60^{\circ}C$ were lower by 0.2% than at $25^{\circ}C$, where as the 70, $80^{\circ}C$ treatments showed a sharp rise from the early stage of fermentation. Soluble solids showed the same aspects with the glycosyl enzymes cases. In reducing sugar, 25, $50^{\circ}C$ treatments were sharply increased from the first day of fermentation while $60^{\circ}C$ treatments began to rise from second day 70, $80^{\circ}C$ were slightly increased after the fourth day. The normally alcohol fermented treatments were 25, 50 and $60^{\circ}C$ 30min. The $70^{\circ}C$ treatments almost did not alcohol fermentation. In the preference tests, taste and total acceptability were high at 25, $50^{\circ}C$ treatments. These results suggest that makgeolli using heat treated nuruk extract also has good taste as well as did not.

• 한국식품과학회지
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• 제28권1호
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• pp.137-145
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• 1996

기업적으로 생산하는 공장의 김치를 시료로 하여 5, 15, $25^{\circ}C$에서 발효하면서 화학적 성분과 함께 젖산균과 효모의 변화를 관찰하였다. 발효온도에 따른 숙성김치의 적정 pH인 4.2에 도달하는 시간은 $25^{\circ}C$의 경우 2일, $15^{\circ}C$의 경우 3일, $5^{\circ}C$의 경우 23일 소요되었다. 젖산량으로 산출한 최적 산도는 pH와 정확하게 일치하지는 않았다. 총균수는 발효온도 $25^{\circ}C$의 경우 2일, $15^{\circ}C$는 6일, $5^{\circ}C$는 12일에 최고 수준에 달하였다. 김치 발효동안 동정된 Lactobacilli 종은 L. brevis, L. plantarum, L. acidophilus와 3종의 미확인 균종이었다. L. brevis, L. plantarum은 $15^{\circ}C$, $25^{\circ}C$ 발효 온도에서 발효 시작에서부터 종결까지 일정수준을 유지하면서 나타났다. Leuconostoc종은 L. mesenteroides subsp. mesenteroides로 동정되었다. L. mesenteroides subsp. mesenteroides는 발효 초기에는 균수가 증가하였다가 모든 발효온도에서 발효 후기에는 급격하게 감소하였다. Pediococcus종은 P. pentosaceus와 1종의 미확인종으로 밝혀졌으며 발효 초기에는 증가하였다가 후에 감소하였다. 발효 중기에 나타난 Streptococcus faecium subsp. casseliflavus와 Aerococcus viridans 또한 김치 발효중에 동정된 균이다. Crytococcus laurenti는 모든 발효온도에서 동정되었고 발효초기에 나타난 후 사라졌다가 $25^{\circ}C$ 발효온도에서만 10일 후에 다시 나타났다.

• 한국식품저장유통학회지
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• 제18권6호
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• pp.986-992
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• 2011

사과식초 제조를 위한 전단계로서 사과주스의 알코올발효 최적화를 실시하였다. 알코올발효 최적화를 위해 중심 합성계획이 사용되었으며, 이 때 독립변수로는 초기 당도(12, 14, 16, 18, 20 $^{\circ}Brix$, $X_1$), 발효시간(48, 54, 60, 66, 72 hr, $X_2$), 발효온도(24, 26, 28, 30, $32^{\circ}C$, $X_3$)로 설정하였으며, 종속변수로는 알코올함량, 환원당 함량, 당도, 산도를 살펴보았다. 발효조건에 따른 사과주스 알코올발효액의 알코올 함량은 3.4~6.4%, 환원당 함량은 1.93~6.24%, 당도는 6.1~13.8 brix로 나타났다. 알코올 함량은 주로 발효온도에 영향을 많이 받았으며, 발효시간이 길고 온도가 증가할수록 증가하는 경향을 나타내었다. 환원당 함량은 주로 초기 당도와 발효온도에 영향을 받는 것으로 나타났다. 초기 당도 15.22 $^{\circ}Brix$, 발효시간 64.97 hr, 발효온도 $31.56^{\circ}C$일 때 알코올 함량의 최대값이 6.4%로 예측되었다.

• 한국축산시설환경학회지
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• 제7권2호
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• pp.137-140
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• 2001

The objective of this study was isolation of halotolerant lactic acid bacteria for fermentation of food wastes. 5 strains of lactic acid bacteria were isolated from fermented foods. Among isolated strains, the strain 5-2 was selected according to the growth characteristics in food wastes containing medium. The selected strain 5-2 was identified as Pediococcus acidilactici based on its biochemical characteristics.