• Food Science and Biotechnology
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• 제16권3호
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• pp.426-433
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• 2007

We analyzed the isoflavone content of domestic soybeans during steaming, boiling, fermentation, germinating cultivation, fermentation, and soybean curd production. The isoflavone content of the beans was reduced by steaming and boiling, and overall reductions ranging from 16.0 to 65.0% of initial isoflavone values were detected. After 4 days of germinating cultivation, the total isoflavones of Eunhakong increased from 1,341 to $2,017\;{\mu}g/g$ and the total isoflavones of Guinunikong increased from 1,284 to $1,535\;{\mu}g/g$. The isoflavone content of the vinegar beans produced from Hwangkeumkong and Black No.1 increased from 1,877 to $1,956\;{\mu}g/g$, and from 885 to $1,956\;{\mu}g/g$ after 8 days of immersion in 4% acetic acid, respectively. During soybean curd production, significant amounts of isoflavones were lost in the whey (30-31 %) and soybean curd residue (15-20%). Only 37.4% of the isoflavones present in the original soybeans remained in the soybean curd with the hot extraction method, and 50.7% of them with the cold extraction method. Soybean curd prepared with whole soybean method, however, retained 80.7% of the initial isoflavones.

• 한국미생물·생명공학회지
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• 제51권1호
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• pp.53-58
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• 2023

Lactococcus lactis HY7803 균주를 대두 발효에 적용하여 맛 성분을 향상시키는 조미료 제조에 대한 이용 가능성을 확인하고자 대두 발효를 진행하였다. 대두발효물의 이화학적 분석 결과에 따르면, L. lactis HY7803 균주를 접종한 대두 발효물은 발효가 진행되면서 아미노태질소 함량, 아미노산 함량이 증가한 반면, 생균수가 감소하였다. 또한 맛성분에 기여하는 아미노산인 글루탐산의 함량을 보면, 발효가 진행됨에 따라 114.99 ± 9.37 pmol/ul에서 138.14 ± 1.76 pmol/ul로 함량이 증가하였고, 글루탐산을 포함한 12개의 아미노산 함량이 음성대조군인 균을 첨가하지 않은 대두발효물에 비해 높았고, Aspergillus oryzae SNU-G를 첨가한 대두발효물과 유사한 함량으로 측정되었다. 따라서 본 연구의 결과는 L. lactis HY7803가 A. oryzae SNU-G의 대체종균으로써 이용 가능하며, 대두 발효를 통해 감칠맛 성분을 생산하는데 기여하는 종균으로써 효과적일 것으로 판단하였다.

• Food Science and Biotechnology
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• 제16권3호
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• pp.451-456
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• 2007

The potential antioxidant activities of methanolic extracts from soybean and rice fermented with Monascus sp. were investigated. M. pilosus IFO 480 and M. anka IFO 478 were screened as a suitable strain to promote the antioxidant activities in soybean- and rice- fermentation. The methanol extracts from soybean and rice after fermenting for 20 days at $30^{\circ}C$ resulted in a significant increase in the antioxidant capacities expressed as radical (ABTS and DPPH) scavenging assay and peroxidation inhibition (%) by thiocyanate method and increased (p<0.01) by a 2.6 to 3.1-fold compared with those of the unfermented products. The average antioxidant potentials of Monascus-fermented soybean extracts (MFSE) were significantly (p<0.01) stronger than Monascus-fermented rice extracts (MFRE). A linear correlations between free radical scavenging activity of MFSE and the total phenolics content (r=0.84) and total flavonoids content (r=0.81) were observed. These results indicated that MFSE exhibited stronger (p<0.01) antioxidant activity and contained significantly higher levels (p<0.05) of phenolics than MFRE.

• 동아시아식생활학회지
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• 제24권5호
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• pp.641-645
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• 2014

This study was performed to investigate the possibility of using three commercial bifidobacteria as a starter for soybean paste fermentation. In order to determine susceptibility to inhibition by high concentrations of salt in soybean paste, cell growth of three strains in sterilized soybean paste was analyzed. Bifidobacterium breve KCTC 5081 was the most resistant to salt, whereas Bifidobacterium bifidum KCTC 5082 showed low cell viability. Conversion efficiencies from glycoside isoflavone to aglycon isoflavone in soybean paste ranged from 11.3~28.6%, with Bifidobacterium longum KCTC 5734 the best strain. Therefore, B. longum KCTC 5734 may be used as a starter for Cheonggukjang fermentation, which is low-salt fermented soybean paste.

• Preventive Nutrition and Food Science
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• 제12권1호
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• pp.29-34
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• 2007

The production of mevinolin, a potent hypocholesterolemic drug, and the bioconversion of isoflavones were investigated in soybeans fermented with Monascus pilosus KFRI-1140. The highest yields of 2.94 mg mevinolins and 1.13 mg isoflavone aglycones per g dry weight of soybean were obtained after 20 days of fermentation. Mevinolin was present in the fermentation substrate predominantly in the hydroxycarboxylate form (open lactone, 94.8$\sim$96.7%), which is currently being used as an hypocholesterolemic agent. The significant (p<0.01) bioconversion (96.6%) of the glucoside isoflavones (daidzin, glycitin, genistin) present in the soybean to the bioactive aglycones (daidzein, glycitein, genistein), with a 15.8-fold increase of aglycones was observed. The results suggest that Monascus-fermented soybean has potential as a novel medicinal food or multifunctional food supplement.

• Journal of Microbiology and Biotechnology
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• 제11권3호
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• pp.428-434
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• 2001

A viscous substance producer strain BS62, which was isolated from conventional Chungkookjang, was examined for its productivity of levansucrase and levan during soybean fermentation at $37{\circ}C$. After one day of cultivation, the enzyme activity reached the highest level, 8 units $ml^{-1}$. Extracts of fermented soybeans were precipitated by ethanol and hydrolyzed by either 0.1 N HCl or invertase, and the hydrolyzates were analyzed using thin layer and ion chromatographies. Fructose was the only sugar detected. This suggest that fructose was derived from the levan produced by the strain BS62 during soybean fermentation. The aerobic, endospore-forming bacterium BS62 was identified as a Bacillus subtilis sp., based on the composition of its cellular fatty acids and phylogeny, which was determined by its 16S rDNA sequence.

• Asian-Australasian Journal of Animal Sciences
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• 제14권11호
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• pp.1564-1567
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• 2001

Hydrolysis of plant protein to non-protein nitrogen (N) or ammonia can reduce quality of silage crops. Heating or non-enzymatic browning is a treatment to inhibit this hydrolysis. This experiment was conducted to examine the effects of pre-heated soybean meal and molasses on the fermentation quality of napiergrass silage. The initial growth of napiergrass was harvested at 85 days of age and immediately chopped into about 1 cm length. About 700 g of the grass was ensiled into a laboratory silo (1.0 liter polyethylene container) and incubated for 30 days at room temperature ($28^{\circ}C$). No additives (control), molasses, soybean meal and molasses + soybean meal treatments were prepared. All additives were non-heated or heated in an oven at $150^{\circ}C$ for 30 minutes before ensiling. Molasses was added at 3% on the fresh weight basis and soybean meal was added at 0.5% N, respectively. After opening the silo, pH, total nitrogen (TN), volatile basic nitrogen (VBN), lactic acid (LA), acetic acid (AA), butyric acid (BA) and dry matter (DM) contents were determined. The data were analyzed statistically by analysis of variance. Compared with control, molasses addition significantly decreased pH value, VBN/TN, AA and BA and increased LA production. Soybean meal addition significantly increased TN and VBN/TN of silage. Both molasses and soybean meal addition significantly reduced pH value, AA, and BA and increased DM and LA contents of silage. The heating of additives was only effective to reduce VBN/TN production compared with non-heated additives in soybean meal and soybean meal with molasses addition.

• 한국식품저장유통학회지
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• 제20권2호
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• pp.199-206
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• 2013

본 연구에서는 땅콩나물 분말을 다양한 농도(0, 0.5, 1.0, 2.0, 3.0%)로 첨가한 요구르트의 품질 특성 및 항산화활성 측정을 실시하였다. 요구르트의 발효 중 pH는 발효시간 및 땅콩나물 분말 첨가량에 의존하여 감소한 반면, 적정산도는 발효시간 및 땅콩나물 분말 첨가량이 증가할수록 산도가 증가하였고 요구르트의 명도는 감소하였으며, 황색도 및 적색도는 증가하는 경향을 나타내었다. 땅콩나물 요구르트의 당도는 땅콩나물 분말 첨가량에 의존하여 증가하였으며, 발효가 진행됨에 따라 감소하였다. 한편, 요구르트의 점도는 발효시간과 땅콩나물 분말 첨가 농도가 증가할수록 높아졌으며, 첨가군의 유산균수는 대조군에 비하여 높게 측정되었다. 땅콩나물 요구르트의 관능평가에서는 질감에 대한 선호도를 제외하고 향미, 색, 맛 및 전반적인 기호도에서 0.5 및 1.0% 땅콩나물 분말 첨가군에서 다른 첨가군보다 높은 선호도를 나타내었다. 요구르트의 항산화활성은 1.0% 이상 땅콩나물 분말 첨가하였을 때 유의적으로 항산화활성이 증가하였다. 이상의 결과를 통해 요구르트를 제조 시 땅콩나물 분말의 첨가는 산 및 유산균과 같은 품질특성을 증가시키고, 항산화 효과와 같은 기능성을 증가시키는 것으로 확인되었다. 특히, 1.0% 농도의 땅콩나물 첨가는 땅콩나물 대두 요구르트 제품 개발시 기능성 및 기호도 향상에 가장 적합한 조건으로 이용될 수 있으리라 생각된다.

• 한국식품과학회지
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• 제39권3호
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• pp.304-308
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• 2007

본 연구에서는 24시간 동안 싹튼 콩을 원료로 하여 콩알 메주를 제조한 후 발효기간에 따른 각종 품질의 변화를 조사하였다. 발효 전 기간 동안 pH는 6.3-6.5로 큰 변화가 없는 것으로 조사되었다. 증자 직후의 아미노태 질소함량은 15.5 mg%였으며, 발효가 진행됨에 따라 급격히 증가하여 발효 48시간째에는 312.9 mg%를 나타내었다. 발효기간별 미생물의 변화를 확인한 결과 곰팡이의 수가 높게 나타난 반면 호기성 세균과 효모의 수는 낮게 나타났는데 이는 메주의 제조 시 Aspergillus oryzae를 접종하였기 때문인 것으로 판단된다. 발효가 진행됨에 따라 유기산 함량은 점차 높아져 발효 48시간째에는 1,067.3 mg%가 검출되었으며 함량별로는 발효 전 기간에 걸처 citric acid가 가장 많이 검출되었다. 유리아미노산 함량은 발효가 진행됨에 따라 함량이 급격히 높아져 발효 48시간째에는 2,513.5 mg%로 발효 전에 비해 5.7배 가량 많이 검출되었다. 함량별로 보면 glutamic acid가 가장 많았으며, aspartic acid, lysine, leucine 및 proline의 순으로 많이 검출되었다. glutamic acid의 총아미노산에 대한 비율은 발효가 진행됨에 따라 점차 증가하여 발효 48시간째에는 21.2%로 나타났다. 총 Isoflavone의 함량은 발효초기에 123.9 mg%로 약간 증가한 후 그 수준을 지속적으로 유지하는 것으로 나타났으며, 발효 전 기간 동안 genistein>daidzein>glycitein의 순으로 나타났다.

• 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.