• Preventive Nutrition and Food Science
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• v.11 no.2
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• pp.166-170
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• 2006

This study was carried out to investigate the fermentation characteristics and optimum conditions for alcohol fermentation of the Korean native mulberry. The yeast strains of S. kluyveri DJ97, La parisienne (Saccharomyces cerevisiae, Netherlands) and Enoferm (Saccharomyces cerevisiae, Denmark) produced higher alcohol concentrations than other strains, and further study was therefore performed with these three species. The optimum additional water content for maximizing alcohol concentration was 250% (v/w). The alcohol concentrations were rapidly increased in the first 4 days under the optimum conditions and reached 13.8% for S. kluyveri DJ97, 14.0% for La parisienne and 14.0% for Enoferm, respectively. Residual sugar concentration was decreased steadily from the beginning of fermentation until 5 days, after which it maintained a constant level. The pH was decreased steadily in the log phase during further maturation. However, the pH underwent a slight decrease after 4 days and then was stabilized during further maturation. Methanol concentrations for the three species used were analyzed after 60 days maturation and were lower than the levels regulated by the food standard. Fusel oils such as n-propanol, iso-butanol, and iso-amyl-alcohol were produced as by-products with the highest production from Enoferm and the lowest from S. kluyveri DJ97.

• Culinary science and hospitality research
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• v.21 no.3
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• pp.232-247
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• 2015

This study was carried out to evaluate the quality of characteristics of the Takju, Yakju, spirit made by various pulse crop Nuruks which were made by Whyangonkuk(whole wheat, mung beans), Naebubijeonkuk mung beans, wheat flour, millet), Daedukuk(whole wheat, soybean). pH, Brix, total acidity, cell numbers of yeast and alcohol content of brews were analysed and flavors, organic acids, sensory evaluation of Takju, Yakju, and spirit were employed to analyze for current study. Results showed that pH value of Whyangonkuk brews during fermentation decreased the lowest, and Brix value also decreased. Total acidity of Whyangonkuk at the initial and final stage of fermentation revealed the most. Alcohol contents of Naebubijeonkuk brew presented the highest at the initial stage of fermentation, but there were no significant differences among Whyangonkuk, Naebubijeonkuk and Daedukuk at the final stage of fermentation. Cell numbers of yeast were found the most in Daedukuk at the first stage of fermentation, and cell numbers started to decrease after 2 days, but there were no significant differences at the final stage(p<0.05). In terms of analysis of flavor components, acetone and n-amyl alcohol were not detected in Takju, Yakju, and spirit. n-butanol was detected the most value followed by i-amyl alcohol. Fusel oil were detected the highest level at spirit, but no differences among Takju, Yakju and spirit. In analysis of organic acids, fumaric acid and formic acid were detected in Takju and Yakju. while 7 kind of organic acids were detected. Lactic acid showed the highest level in organic acid analysis. Takju and Yakju made by Whyangonkuk showed the highest score, and Daedukuk showed the opposite result but there were no differences in spirit made by Whyangonkuk, Naebubijeonkuk, and Daedukuk. As a result of this study, Whyangonkuk presented the most desirable Nuruk.

• Preventive Nutrition and Food Science
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• v.3 no.3
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• pp.230-233
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• 1998

Acetic acid producing bacteria were isolated from deastringent persimmon vinegar and the major bacterium was identified using morphological and biochemical tests. Acetobacter sp. AH-1 was motile, gram negative rod with catalase positive and oxidase negative. The strain can grow up to 5 % ethanol and 2% NaCl as well as 25% glucose. Optimum temperature and pH for growth were 3$0^{\circ}C$ and 5.0, respectively. Volatile constituents of persimmon vinegar were analyzed by purge and trap sampling . Acetic acid adn alcohol were the largest volatile compounds quantitiatively in persimmon vinegar. Among alcohols, 20methyl-1-propanol, isoamyl alcohol and amyl alcohol were detected. Isovaleradehyde and benzaldehyde for aldehyde, isoamyl acteate, ethyl formate, propyl aceetate, and ethyl acetate for esters were likely to contribute to persimmon vivegar flavor.

• Journal of the Korean Society of Food Culture
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• v.18 no.2
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• pp.111-122
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• 2003

This studies were performed to develop a Korean traditional folk liquor namely Gangha-ju has been prepared at Bosung district in Korea, and manufacturing conditions and anti-oxidation activity and anti-microbial activity of Gangha-ju were investigated. Ethyl-alcohol 20% and 30% Gangha-ju were brewed with glutinous rice wine, distilled liquor and 6 herbs of ginger, cinnamon, etc. Chemical and physical properties of 30% Gangha-ju were acidity 0.22, pH 4.31, amino acidity 3.26, transmittance 59 and conductivity $911\;{\mu}s/m$, and 20% Gangha-ju were 0.43, 4.20, 6.26, 62 and $924\;{\mu}s/m$. Volatile flavor compounds of ethyl alcohol, acetic acid, butanol, n-amyl alcohol, iso-pentyl alcohol, ethyl acetate, butyl acetate, acetaldehyde and furfural were detected, and main aroma compounds of Gangha-ju were isopentyl alcohol and ethyl acetate. Anti-oxidation activity by DPPH method was evaluated 31.32%, and nitrite scavenging effect was 31.79%. Anti-microbial activity against several microorganisms was pronounced strong activity over a wide range of test organisms, and Leuconostoc mesenteroids and Salmonella Ttyphimurium, Staphylococcus epidermidis were found to be more sensitive to Gangha-ju than Escherichia coli and Aspergillus flavus.

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.3
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• pp.361-365
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• 2007

This study was conducted to improve the Prunus mume vinegar production. The most suitable concentration of the Prunus mume juice was 6%. Static fermentation was a more suitable process for acetic acid fermentation of the Prunus mume vinegar than shaking fermentation. Major components of the organic acids were acetic, citric, tartaric and malic acid at 4.2, 1.2, 0.3, and 0.1%, respectively. Also, major components of the free sugars were glucose and fructose, and 80.96 mg% of asparagine was included in the Prunus mume vinegar as a main free amino acid. Alcohol components of the Prunus mume vinegar were n-propyl alcohol, iso-butyl alcohol, n-butyl alcohol, iso-amyl alcohol, and n-amyl alcohol.

• Applied Biological Chemistry
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• v.30 no.3
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• pp.264-271
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• 1987

Baikhaju, Nockpaju, Dongdongju and Chungmyungju of the traditional Yakjus - the native alcoholic beverage of Korea - with the different fermentation methods were brewed and the volatile odor components were analized by gas chromatography methods of headspace gas. The general constituent content in them was different a little, and formaldehyde, acetone, acetaldehyde, ethylacetate, ethylalcohol, n-propanol, iso-butanol, iso-amylalcohol, diacetyl and dimethyl sulfide were separated and quantified into the volatile aroma components. The contents of acetaldehyde, ethylacetate and n-propanol were $17{\sim}73ppm$, and iso-amylalcohol were $418{\sim}925ppm$. The contents of formaldehyde and acetone were $0{\sim}2.15ppm$, and that of diacetyl and dimethyl sulfide were $0.032{\sim}1.012ppm$, and $5{\sim}65ppb$.

• Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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• 2003.10a
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• pp.220.1-220
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• 2003

전분질원으로서 밀가루와 찹쌀을 단용 (A : 전량 밀가루 사용, D： 전량 찹쌀 사용) 또는 혼용(B: 밀가루 75%, 찹쌀 25%, C: 밀가루와 찹쌀을 각 50%사용)하여 담금한 고추장의 성분을 분석 한 결과는 다음과 같다. 숙성과정중 조단백질과 아미노태의 질소함량은 대체적으로 A,B,C,Drn의 순으로 높았고, ethyl alcohol은 D,C,B,A 구의 순으로 높았다. pH는 A 구에서 다소 높았으나 수분과 식염은 시험구간에 차이가 없었다. 90일 숙성 고추장중의 유리당은 glucose, fructose, maltose, rhamnose가 검출되었고, 이중 glucose는 양적으로 가장 많았다. 또한 glucose는 A 구에서, fructose는 B 구에서 각각 높았다. 숙성고추장의 알코올류로서 n-propyl, iso-buthyl, iso-amyl alcohol이 검출되었으며, 이들 함량은 3.2mg%이하로 시험구간에는 큰 차가 없었다.

• Journal of the Korean Chemical Society
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• v.11 no.1
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• pp.8-11
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• 1967

A method of determination of gold in ores has been established: Disolved ore solution is evaporated to dryness, redissolved with 0.1N HCl then chloroaurate formed is adsorbed on anion exchange resin, Dowex $1\;{\cdot}\;{\times}4$. The resin is ignited and the residue is dissolved with HCl-$HNO_3$. After evaporation of the acid, and then dilution with water, sodium azide is added. The gold is extracted with amyl alcohol from the solution buffered to pH 6. The gold is determined by measuring absorbancy of the alcohol layer spectrophotometricaly at $385m{\mu}$. Various factors, HCl concentration, amount of the resin rate, if adsorption, foreign ions, effecting to the method, have been examined. This method seems to be satisfactory for the determination of gold presented dawn to 1g per metric ton in ore.

• Applied Biological Chemistry
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• v.39 no.4
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• pp.249-254
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• 1996

The volatile flavor components in mash of nonglutinous rice Takju brewed with or without addition of the starter were determined by GC and GC-MS using polar column. Various kinds of volatile components including alcohols(10), esters(9), organic acids(2) and aldehydes(7) were found in mash of nonglutinous rice Takjus. At the beginning stage of fermentation, 3 to 7 volatile flavor components were detected. The number of volatile flavor components were increased to 26 of to 28 after 16 days fermentation. Early in the brewing, just 3 kinds of flavor components including ethyl acetate, ${\beta}-phenylethyl$ acetate and acetic acid were detected in mash of nonglutinous rice Takju without the addition of the starter, when starter is added additional compounds of alcohol including ethanol were detected, which is suggested to be the effect of flavors originated from the starter. The common flavor compounds through the entire process of fermentation in mash of nonglutinous rice Takju were ethyl acetate, ${\beta}-phenylethyl$ acetate and acetic acid. The relative amount(peak area %) of flavor components were changed with the fermentation period, but the major volatile flavor components were ethyl alcohol, iso-amyl alcohol, hexenyl alcohol, ethyl acetate, ${\beta}-phenylethyl$ acetate and ${\beta}-phenylethyl$ alcohol. The relative amount(peak area %) of ethyl alcohol was the highest in mash of nonglutinous rice Takju with addition of starter. When the starter was not added in the mash of nonglutinous rice Takju, any alcoholic components were not detected in the early stage of fermentation. But the percent of peak area hexenyl alcohol was the highest after 16 days fermentation. Especially few sorts of ester were detected in mash of nonglutious rice Takju without addition of starter by 3 days fermentation.

• Food Science and Preservation
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• v.17 no.1
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• pp.36-41
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• 2010

Fermentation characteristics of yakju prepared with addition of Opuntia ficus indica were examined, with respect to the nature and concentration of additional added materials. The pH level began to decrease after the secondary brewing stage and the total acid content increased during fermentation. The level of reducing sugars in yakju prepared with Opuntia ficus indica increased at the first brewing stage and then slowly decreased after 4 days of fermentation. The ethanol content of supplemented yakju rapidly increased during the initial 6 days of fermentation, to a maximum content of 17.1% after 14 days. The free sugar content was higher in yakju fermented with Opuntia ficus indica stem compared with fruit. The level of organic acids increased as the amount of Opuntia ficus indica material increased. Organic acid level increased during fermentation and lactic acid was the main organic acid in yakju fermented with Opuntia ficus indica. Sixteen volatile compounds were found by GC-MS in supplemented yakju. The most prominent volatile component was iso-amyl alcohol, followed by butyl alcohol and methyl esters. The DPPH radical-scavenging activity of yakju fermented with Opuntia ficus indica stem was higher than when yakju was prepared with fruit. Sensory scores of yakju fermented with 20% (w/v) fruit and 10% (w/v) stem were greater than those of yakju prepared by other treatments.