• 한국식생활문화학회지
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• 제34권3호
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• pp.353-360
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• 2019

To optimize the fermentation period of lightly salted Oiji, 3% salt was added to cucumbers that were fermented at $27{\pm}1^{\circ}C$ for 3, 4, 5, 6, or 7 days, after which their physical properties (moisture content, salinity, pH, acidity, hardness) and sensory characteristics (acceptance test, difference test) were evaluated. The moisture content was highest at day 6. Hardness slowly increased as fermentation time increased, but not significantly. The pH was highest after 3 days of fermentation, and tended to decrease as fermentation time increased, with the largest drop occurring between 4 and 5 days, and the lowest pH occurring between 6 and 7 days. Acidity was lowest after day 3 of fermentation and highest after day 7. Acidity tended to increase as fermentation period lengthened. The L-value tended to decrease as salt concentration increased. The a-value declined from day 3 to day 5, then increased significantly by day 7. The b-value was highest after 7 days, with a tendency to increase as the fermentation progressed. Acceptance test results were highest for taste and overall acceptance after 5 days of fermentation. The difference test showed that the optimal lightly salted Oiji fermentation period was approximately 5 days. These results indicate that lightly salted Oiji fermented for 5 days produced the highest acceptance.

• 한국산업융합학회 논문집
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• 제22권1호
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• pp.61-69
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• 2019

All the parts of lotus, including the seed, rhizome, leaf, stalk, petal, anther, pericarp, and fruit receptacle, have been used in traditional medicine system as a health beneficial supplement. However the most usually used from lotus plant is only the root. Therefore in this study, it will be discussed more the utilization of other parts of the lotus, namely the flower of lotus. The petals and stamens of lotus actually are also rich in bioactive components such as flavonoids and alkaloids, are used in the treatment of tissue inflammation, cancer, skin disease, and also for us as antidotes. One of the biotechnological process that can be used to improve the nutritional content, sensory, and also antioxidant activities is fermentation process. The final product desired from the fermentation process in this study is vinegar. The microbial strain powder used is Uinkin fermented powder with three variations of fermentation. The variations given in this study were initial sugar 32%, 24%, and 14% with the same fermentation temperature, $35^{\circ}C$ for 3 months. The results obtained showed that the pH value and sugar content of products during the fermentation process were decreasing during the fermentation process, with total polyphenol content of $283.7{\pm}97.6mg/100g\;QAE$, and total flavonoid content of $3.3{\pm}0.0mg/100g\;QAE$. For the DPPH radical scavenging ability of the fermentation product also increased in a concentration dependent manner, with ORAC activity of the product showed a high activity of $20.7{\pm}0.41{\mu}M$ TE. Therefore, fermentation process can be the one of method for improving the product. The efficiency of lotus flower vinegar fermentation can be reached with an initial sugar condition of 25% (sample B).

• 상하수도학회지
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• 제21권4호
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• pp.467-475
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• 2007

This study was conducted to examine temperature effects on hydrogen production in anaerobic fermentation. 18 batch reactors were operated at mesophilic ($35^{\circ}C$) and thermophilic conditions ($55^{\circ}C$) to achieve maximum hydrogen production in anaerobic fermentation. Optimum hydrogen production conditions were also investigated at each temperature. Different trends were observed regarding pH effects on hydrogen production. This effect was not significant for mesophilic fermentation ($35^{\circ}C$). In this case, pH may not drop to interfere hydrogen production during the test. However, hydrogen production decreased without pH control for thermophilic condition ($55^{\circ}C$). Effects of heat treatment were observed for both fermentation process. Hydrogen production with heat treatment was higher than hydrogen production without heat treatment for both fermentation processes. The amount of produced hydrogen for each substrate concentration with temperature changes showed that more hydrogen was produced at $35^{\circ}C$ than at $55^{\circ}C$.

• 한국조리학회지
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• 제6권3호
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• pp.357-371
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• 2000

Changes of Microflora, enzyme activity, and contents of several taste compounds in traditional Kanjang(Korean Soy Sauce) with the variation of fermentation jars and Meju(fermented soybean brick)concentration were studied. Substitution possibilities of clay jar with glass jar and improvement possibilities of taste and nutritional value with increased Meju concentration were examined. (1) Aerobic bacteria and lactic acid bacteria were enumerated during fermentation and ripening period. But yeast and molds were hardly isolated. The number of viable cells showed small changes during fermentation and ripening period. (2) Isolated Aerobic bacteria were identified as Bacillus subtilis, Bacillus lichenformis, and lactic acid bacteria were identified as Lactlbacillus lactis lactis and lactobacillus brevis. (3) The activities of $\alpha$-amylase and $\beta$-amylase increased during fermentation period, but did not show any trend by fermentation jars or Meju concentrations. Protense activity showed small difference among four samples, and increased during the fermentation period.

• 한국미생물·생명공학회지
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• 제27권3호
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• pp.246-251
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• 1999

To extend the storage period and to inhibit contamination of Kimchi by Escherichia coli, conditions of Kimchi brining and effects of the fermentation starter, halophilic Lactobacillus HL-48 were investigated. Optimum brining condition for Kimchi was accomplished in 15% NaCl and at pH2.5-3.0 adjusted by lactic acid. Starter-treated Kimchi showed pH 4.2 after 18hr fermentation, while the pH of starter-untreated Kimchi resulted in 3.3. After 36hr fermentation, the number of E. coli in starter-treated Kimchi was found clearly to decrease and not detected macroscopically, but contamination of E. coli (5.3$\times$103CFU/ml) was observed in starter-untreated sample. Organic acids in Kimchi contained organic acids such as oxalic acid, citric acid, malic acid and lactic acid. among ther, lactic acid content was remarkably high in the early fermentation stages. However, from 24hr fermentation, lactic acid content of starter-untreated Kimchi was higher than that of starter-treated Kimchi.

• Journal of Microbiology and Biotechnology
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• 제4권4호
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• pp.333-337
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• 1994

In order to develop the whey beverage, we examined the optimum conditions for alcohol fermentation by Kluyveromyces tragilis ATCC 46537. The optimum conditions for alcohol production by K. fragilis ATCC 46537 were as follows; pH 4.5, $30^{\cir}C$, with a supplement of 50 g/l of lactose. To develop a continuous production of alcohol from whey, we compared batch fermentation with continuous iermentation in conjunction with UF system. Batch fermentation produced 11.0 g/l of alcohol, whereas pseudocontinuous and continuous fermentation with UF system produced 8.5 g/l of alcohol. To increase the alcohol production, we added 50 g/l of lactose to both fermentations. Batch fermentation with lactose supplement produced 15.7 g/l of alcohol and continuous fermentation with lactose supplement in conjunction with UF system produced 15.0 g/l of alcohol. These results clearly demonstrate that the UF system can be used to increase the alcohol production from whey, supplemented with exogenous lactose.

• 한국미생물·생명공학회지
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• 제22권2호
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• pp.217-221
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• 1994

The essential oil of astringent persimmon leaves was extracted by a gas co-distillation method and its effects on Kimchi fermentation were examined. The changes of pH and titratable acidity of Kimchi during fermentation at 15$\circ $C generally decreased by the addition of essential oil of astringent persimmon leaves, and the growth of microorganisms associated with Kimchi fermentation was also inhibited. The fermentation time of Kimchi reaching to the maximum number of cell counts was greatly extended as compared to that of the Kimchi fermented without the addition of essential oil. The greatest antimicrobial activity activity of essential oil of persimmon leaves was shown against Lactobacillus plantarum among varoius bacteria associated with Kimchi fermentation. The antimicrobial activity of essential oil against Saccharomyces cerevisiae was much higher then that against lactic acid bacteria such as L. plantarum.

• Fisheries and Aquatic Sciences
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• 제3권1호
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• pp.44-48
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• 2000

In order to utilize chum salmon returned in the east coast of Korea, the changes in the properties of Yeonual-jeot (salted salmon roe) fermented at different temperatures were measured for obtaining the basic data for its commercial production. Moisture content of salted salmon roe was significantly lower than raw salmon roe, while other proximate components were in the reverse. pH was constant for 56 days fermentation at $5^{\circ}C$, but decreased with fermentation Reriod at 10 and $15^{\circ}C$. The contents of amino-nitrogen and VBN were almost in constant at $5^{\circ}C$ up to 28 days of fermentation, but increased very slowly at $10^{\circ}C$ and moderately at $15^{\circ}C$. TBA value, and the numbers of total viable cells and lactic acid bacteria increased over all fermentation periods, more at higher fermentation temperatures.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2005년도 생물공학의 동향(XVII)
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• pp.319-323
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• 2005

This study is concerned with development of efficient culture methods for lactic acid fermentation of Lactobacillus sp. RKY2. The cell-recycle repeated batch fermentation using cheese whey and corn steep liquor as raw materials was tried in order to further enhance the productivity of lactic acid. In addition, fermentation efficiencies could be considerably enhanced by cell-recycle continuous culture. Through the cell-recycle repeated batch fermentation, lactic acid productivity was maximized to 6.34 $g/L{\cdot}h,$ which corresponded to 6.2 times higher value than that of the batch fermentation. During the cell-recycle continuous fermentation, the last dry cell weight at the end of fermentation could be increased to 25.3 g/L.

• 한국축산시설환경학회지
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• 제4권2호
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• pp.175-182
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• 1998

For the recycling of swine takes 2 different steps in fermenting procedure, acidogenic reactor and methanogenic reactor, the activity of involved microbes can be maintained at the maximum level. This study showed applying 2 separate steps in anaerobic fermentation has improved fermenting efficiency over the conventional 1 step fermentation. Accordingly, the results are coincident with the hypothesis in which 2 steps acidogenic and methanogenic reactor fermentation is more efficient than conventional (1 step) fermentation that makes poisonous materials be obviate and abate. And the results also get the effective performance in the production of methane gas.