• Journal of the East Asian Society of Dietary Life
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• v.24 no.6
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• pp.811-818
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• 2014

The quality characteristics and antioxidant activities of makgeolli added with different amounts of pomegranate powder (0%, 5%, 10%, 15%, 20%) were investigated. Although pH was reduced with increasing concentrations of pomegranate powder, all pH values rapidly decreased for 2 days, and then gently increased afterwards. Total acidity increased until 3 days of fermentation and then slowly increased. Sugar and reducing sugar contents reached maximum levels after 1 day of fermentation and gradually decreased until 7 days. Alcohol content remarkably increased until 2 days and gradually increased until 7 days. The addition of over 10% pomegranate powder increased yeast count until 3 days of fermentation, followed by a decrease. In the sensory evaluation, color, flavor, sweetness, and overall acceptance decreased with increasing concentrations of pomegranate powder, and sourness and bitterness slightly increased. Early antioxidant activity improved according to the concentration of pomegranate powder, but addition of 15% and 20% pomegranate powders reduced antioxidant activity from 3 days of fermentation. In conclusion, addition of 10% pomegranate powder would be the most suitable to manufacture pomegranate makgeolli.

• BMB Reports
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• v.38 no.3
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• pp.294-299
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• 2005

In this report, we describe the high-yield secretory expression of the recombinant human anti-HBsAg Fab fragment from Pichia pastoris that was achieved by co-integration of the genes encoding the heavy and light chains (both under the control of alcohol oxidase promoter) into the genome of the yeast cells. The fed-batch fermentations were carried out in a 5 L scale. Both chains of the Fab were successfully expressed upon methanol induction. The absorbance ($OD_{600}$) of the broth can reach 350~500 at the end of fed-batch phase. After the induction, the expression level of the recombinant Fab (soluble) reached 420~458 mg/L. The recombinant Fab fragment was purified from the crude culture supernatant by ion exchange chromatography and the purity of the recombinant Fab fragment was over 95%. The affinity activities of the crude fermentation supernatant and the purified Fab were analyzed by indirect ELISA, which showed that the purified recombinant Fab fragment had high affinity activity with hepatitis B surface antigen.

• Journal of the Korean Society of Food Science and Nutrition
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• v.29 no.2
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• pp.224-230
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• 2000

In order to study the quality of uncooked-colored wine by using polished black rice(PBR) and glucoamylase, the mixture ration of PBR ws investigated. The growths of yeast and lactic acid bacteria, pH and alcohol concentration of the colored wine prepared by adding PBR in the range of 20 to 100% were higher than those of polished rice only, whereas the contents of residual sugars, total free amino acids and fusel oil of the colored wine were lower. The colored wine prepared by 20% PBR and that of over 80% PBR showed a light red color and a dark red, respectively. The optimal addition ratios of PBR evaluated by palatability of color and flavor, and sensory overall quality was 40 to 60%.

• KSBB Journal
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• v.4 no.1
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• pp.21-30
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• 1989

Lauryl alcohol was used as extracting solvent of ethanol, and its toxicity on the free cells or immobilized cells was tested. To increase ethanol productivity, extractive fermentation method combined with ethanol fermentation and ethanol recovery was applied to the immobilized batch and continuous fermenter. As the concentration of LaOH was increased, the lag phase became longer, but specific growth rate did not change greatly. And a cell entrapment technique could protect the yeast cells against both substrate inhibition and solvent toxicity. When the glucose concentration was 400 g/l and the LaOH/fermentation medium ratio was 4, total ethanol productivity increased with the enhancement of LaOH volume, and maximum productivity was 2.75 g/l.hr in the immobilized batch fermentation.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.10
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• pp.1531-1537
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• 2015

This study was performed to investigate the quality characteristics of Takju under different storage temperatures ($4^{\circ}C$ and $20^{\circ}C$) and alcohol contents (6%, 8%, 10%, and 12%) during 90 days of storage. The counts of yeast were lower in Takju samples stored at $4^{\circ}C$ than in those stored at $20^{\circ}C$ after 90 days of storage. No significant differences were observed for total acidity and free amino acid contents in Takju stored at $4^{\circ}C$ during 90 days of storage. Lactic acid contents in Takju stored at $4^{\circ}C$ changed little after 90 days of storage from 1,883.5 mg/L to 1,914.6 mg/L, whereas those in Takju stored at $20^{\circ}C$ increased to 4,736.1 mg/L after storage. Free amino acid contents in Takju stored at $20^{\circ}C$ increased after 90 days of storage regardless of alcohol content. Thus, we concluded that the shelf-life of Takju could be extended more than 30 days, currently the most common shelf-life of Takju, when stored at $4^{\circ}C$.

• Microbiology and Biotechnology Letters
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• v.38 no.1
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• pp.46-52
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• 2010

Yakju, a Korean traditional alcoholic beverage, is made from glutinous-rice flour or rice starch with nuruk. In this study, we investigated that fermentation characteristics in yakju was made with glutinous rice and pretreatment. The yeast and nuruk were used Y90-9 and SP1800 (a kind of improved nuruk), respectively. pH and brix degree of yakju, brewed with glutinous rice flour by heating, were higher than the others during fermentation process. Total acid contents were 0.2~0.3 and the highest alcohol degree (15.75%(v/v)) was fermented glutinous rice flour by heating. Reducing sugar contents were 3.5-3.9 mg/mL. Yakju, which brewed with glutinous rice flour, of amino acid degree, UV absorbance and color degree was higher than yakju which brewed with glutinous rice starch. Succinic acid was the highest organic acid among 6 organic acids and free sugar contents described as glucose > maltose > fructose. Twenty one components were identified including 3 alcohols, 17 esters and one aldehyde. Of these, ethyl palmitate, which was described as mild flavor, was the highest %area except ethyl alcohol. Overall, the fermentation performed using glutinous rice flour by heating and improved-nuruk showed the best results for yakju production.

• Food Science and Preservation
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• v.24 no.5
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• pp.714-724
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• 2017

Soju is a Korean traditional distilled alcoholic beverage produced from mashes various crops and Nuruk which is cultured with wild microorganisms. This study was conducted to investigate rice-Soju brewing characteristics of yeasts isolated from Korean traditional Nuruk. The general components of rice (Hanarumbyeo) raw materials were 14.7 g of water, 6.8 g of crude protein, 0.9 g of crude lipid, 0.4 g of crude ash, and 76.5 g of carbohydrate in 100 g. Saccharifying and proteolytic activities in Hanarumbyeo ipguk (solid-state culture of Aspergillus luchuensis) were also determined. The alcohol content of the fermented wash from isolates was 15.37-16.58% (v/v), which is 16.7-36.0% higher than that of industrial yeasts (12.33-13.19%). Reducing sugar contents were 2.04-3.92 and 7.92-8.78 g/100 mL in the isolates and industrial yeasts, respectively. The isolated yeasts showed 25.2-52.7% higher yield of distillates (41% alcohol) compared to industrial yeasts. Forty-one components were detected in the rice distillated Soju (25% alcohol) and principal component analysis revealed differences between the isolated and industrial yeasts with respect to the contents of i-BuOH, isobutanal diethyl acetal, ethyl caprate, and tetradecanoic acid.

• The Korean Journal of Mycology
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• v.15 no.4
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• pp.260-267
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• 1987

The effect of Ganoderma lucidum extract on Saccharomyces cerevisiae growth and physiology has been investigated. S. cerevisiae was inoculated in Henneberg solution medium into which 0, 0.1, 0.5 or 1.0% extracts of G. lucidum were added respectively and it was fermented at $30^{\circ}C$ for 5 days, respectively. Cell number of S. cerevisiae has increased according to the concentration as in order of distilled water(Dw) extracts 1.0% added>ethanol(Et) extracts 1.0% added>Dw extracts 0.5% added>Et extracts 0.5% added>Dw extracts 0.1% added>Et extracts 0.1% added group compared to control group(extracts 0% added) and in Dw extracts 1.0% added group the number has increased than those of control group after the fermentation of 72 hours. Weights of dried yeast cell have increased in each treated group than those of control group and it increased about 1.7 times in each Dw 1.0%, Et 1.0% group than those of control group after fermentation of 120 hours. The more the extracts of G. lucidum was added, the more alcohol levels increased during fermentation. The rate of carbon dioxide production per G. lucidum extract medium was faster than those of control group as G. lucidum extract was increasingly added.

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.3
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• pp.444-449
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• 2011

Blueberry Makgeolli was made with rice by adding different amounts of blueberries, and the fermentation characteristics of Makgeolli were studied during the fermentation process. The pH was the highest (6.6) at the beginning of the fermentation and decreased when the ratio of blueberries increased. The pH was remarkably reduced until the second day, and remained constant until the seventh day of fermentation. The total acidity was significantly increased until the fourth day of fermentation, and remained constant until the seventh day. Sugar contents ($^{\circ}Brix$) and reducing sugar reached the maximum after 2 days of fermentation, and gradually decreased until the seventh day. Alcohol content of control (0% blueberries) increased continuously until the seventh day of fermentation and was at 13.4%. Alcohol content of 20% blueberry Makgeolli reached the maximum on the 4th day of fermentation and slowly decreased to 10.2% until the seventh day. Total viable bacterial cell counts and yeast cell counts showed the maximum values at the third day of fermentation. In sensory evaluation, the color of the control sample was the most favored by the panelists whereas 20% blueberry sample was the least favored. There were no significant differences in flavor and taste, but overall preference was high in Makgeolli with less than 10% of blueberries.

• Korean journal of food and cookery science
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• v.21 no.2 s.86
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• pp.263-269
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• 2005

Citrus juice, a concentrate manufactured by the Jeju Provincial Corporation, was converted into vinegar orderly by alcohol and acetate fermentation. The juice with 6 folds dilution by distilled water was used as the sole nutrient source through out experiments. Diluted juice contained $12.96^{\circ}Brix$ of total sugar, $0.632\%$ of total acid and $20.23{\mu}g/m{\ell}$ of hesperidin. Naringin was not detected from the juice. Citrus wine having $5.6\~6.3\%$ alcohol was produced from diluted juice by 3 days of fermentation at $28^{\circ}C$. A kind of malomelo yeast CMY-28 was used for wine fermentation. The wine was succeedingly fermented for 8 days at $30^{\circ}C$ after inoculation of seed vinegar which contained active cells of acid producing bacteria CV1. Inoculum size of seed vinegar was controlled to $10\%$(v/v) of citrus wine. The wine converted into vinegar by the fermentation. Citrus vinegar, the final product of fermentation, was colored with very thin radish-yellow and transparent. It's acidity ranged between $5.8\~6.2\%$ as acetic acid. The vinegar got the best score by sensory test among several natural fruit vinegars. It was clear from the results that citrus vinegar in high quality could be produced from concentrated citrus juice, however fermentation conditions should be improved to reduce the amount of reducing alcohol.