• Microbiology and Biotechnology Letters
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• v.30 no.3
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• pp.216-222
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• 2002

To Produce the modified Cheongiu that has high ethanol content, an ethanol-tolerant strain Saccharo-myces cerevislae SE2l1 was screened from Saccharomyces cerevisiae Kyokai No. 10 strain. The isolate showed faster growth than in the medium containing 10% ethanol compared with original strain. The isolate produced a higher concentration of ethanol and showed higher resistance to ethanol, high osmolarity and heat than the original strain. The analyses of yeast membrane components indicated that there were no significant changes in composition of sterols and phospholipids between the isolated and the original strain. However, during the fermentation, the iso-lated strain could change the fatty acid composition in the membrane more rapidly in the direction of decreasing membrane unsaturation and accumulate more trehalose in the cell than the original strain. These data suggest that the ability to change its membrane fatty acid composition and to accumulate trehalose may make the isolated strain easily adapt to changes in external condition.

• Korean Journal of Food Science and Technology
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• v.34 no.1
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• pp.30-36
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• 2002

To use overproduction muskmelon effectively, muskmelon vinegar was prepared by two stage fermentations of alcohol and acetic acid. In the alcohol fermentation using muskmelon, alcohol content showed maximum value (7.47%) in $17.83^{\circ}Brix$ of initial sugar concentration and 82.65 h of fermentation time. Acetic acid content in alcohol fermentation revealed minimum value (0.46%) in $12.17^{\circ}Brix$ of initial sugar concentration and 60.56 h of fermentation time. The fermentation conditions for minimum residual sugar were $10.02^{\circ}Brix$ of initial sugar concentration and 105.61 h of fermentation time. The optimum conditions predicted for each corresponding physical properties of acetic acid fermentation were 200 rpm (agitation rate), 250 h (fermentation time) in acetic content and 200 rpm, 150 h in residual alcohol content.

• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.3
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• pp.359-365
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• 2006

Changes in isoflavone and oligosaccharides, and some physicochemical properties of Chokong, a pickled and dried soybeans, were investigated during pickling in brewed vinegar at $20^{\circ}C$. The used soybeans were 24 hr germinated soybeans, which was maximumly increased in isoflavone content during germination. The isoflavone contents were significantly increased by approx. 80% in both glycosides and aglycone type of isoflavone after 20 day of pickling at $20^{\circ}C$. The isoflavone values of germinated Chokong were significantly higher than those of ungerminated ones. Pickling the soybeans in vinegar resulted in a rapid initial decrease in oligosaccharides, Particularly in raffinose and stachyose. The pH and soluble solids contents in vinegar increased markedly and L values decreased during initial pickling of 24 hr.

• Korean Journal of Medicinal Crop Science
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• v.9 no.4
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• pp.290-294
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• 2001

Sambaekcho wines were fermented with 5% improved Nuruk, 120% brewing water, and powdered leaf or root as an additive, then the contents of several important phenolics were examined. As the fermentation progressed, the contents of total and flavonoid phenolics, and quercetin-related substances of the Sambaekcho wines increased continuously. The contents of the functional components of the Sambaekcho wines with powdered leaf were much higher than those of the Sambaekcho wines with powdered root, indicating leaf was more adequate than root in making Sambaekcho wine.

• Journal of the East Asian Society of Dietary Life
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• v.26 no.2
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• pp.125-140
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• 2016

We analyzed the cultural characteristics of isolated brewing fungi for developing fermentation starters. In a previous study, we collected 87 domestic nuruk, from which 481 fungi strains were isolated and 11 were selected showing improved productivity. After culturing these 11 fungi strains in several types of media, temperatures, carbon and nitrogen sources, Rhizopus sp. grew well in MEA, ME20S, PDA medium while Aspergillus sp. grew well in ME20S and YES. Both Rhizopus sp. and Aspergillus sp. survived well at optimal growth temperatures of 30 and $37^{\circ}C$. Rhizopus sp. utilized lactose, glucose and peptone sources while Aspergillus sp. utilized glucose, mannose, fructose and yeast extract sources. ${\alpha}-Amylase$ activity was excellent in L. ramosa CN044, R. oryzae 82-7(MEB), R. oryzae CN174 and A. oryzae 58-11(WEB) culture extracts. This study suggests that R. delemar 26-4, 58-8 and A. oryzae 78-5, 37-7 might be appropriate fungi strains for fermentation starters based on development of large fungi bodies and their good enzyme activities.

• Journal of the East Asian Society of Dietary Life
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• v.27 no.3
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• pp.348-363
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• 2017

We analyzed the mixed culture characteristics of isolated brewing fungi obtained from Korean traditional nuruk for their development as fermentation starters. In a previous study, we selected appropriate fungi strains based on their large fungi bodies and strong enzyme activities. These fungi strains were mixed cultured under various combination of ratios, pHs and temperatures. As a result, total acidities of R. delemar mixed culture media were higher than those of A. oryzae cultured at $20^{\circ}C$ and $37^{\circ}C$. The pHs of A. luchuensis 34-1 and A. oryzae 37-7 as well as R. delemar 58-8 and A. oryzae 37-7 mixed culture media gradually increased with the culture period. On the contrary, total acidities of the mixed culture media gradually decreased. ${\alpha}-Amylase$ activities of R. delemar 26-4 and R. oryzae 82-7 mixed culture media were strong at $20^{\circ}C$ and pH 4, glucoamylase activities of R. delemar 58-8 and A. oryzae 37-7 were strong at $37^{\circ}C$, pH 3 and 1:2 ratio, and acidic protease activities of R. delemar 26-4 and A. oryzae 78-5 were strong at $20^{\circ}C$, pH 4 and 1:4 ratio. This study provides the optimal mixed culture conditions for fermentation starters based on changes in pH and total acidity, favorable enzyme activities, and fungi varieties.

• Korean journal of food and cookery science
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• v.10 no.1
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• pp.1-7
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• 1994

Major quality parameters(organic acids, alcohols, fusel oil and sensory characteristics) of traditional Ewhaju were investigated during brewing. In organic acid contents at immediately after brewing, lactic acid was 155.1mg％, malonic acid was 5.4mg％, succinic acid was 8.9mg％, acetic acid was 7.6mg％, oxalic arid was 1.3mg％, citric and tartaric acid was 27.8mg％ and pyruvic acid was 4.8mg％ but in 100 days after brewing and one year aged, lactic acid was 1763.3 and 3059.3mg％, malonic acid was 12.3 and 19.3mg％, succinic acid was 11.5 and 23.1mg％, acetic acid was 29.2 and 73.1mg％, oxalic acid was 0.6 and 0.2mg％, citric and tartaric acid was 298.3 and 639.6mg％, and pyruvic acid were 1.1 and 0.3mg％, respectively. All the alcohol contents increased as the fermentation period increased ; the ethyl alcohol was only 0.05fe at immediately after brewing. In the alcohols content of Ewhaju at 100 days after brewing, the ethyl alcohol, methyl alcohol n-propyl alcohol and iso-butyl alcohol were 5.13ft, 47.56 ppm, 37.25 ppm and 19.51 ppm, respectively, Also in the one year aged Ewhaju, the ethyl alcohol was 9.39f), methyl alcohol was 36.34 ppm, Fusel oil was not detected in the first stage of brewing, but it was detected 1.12mg％ at 100 days after brewing and 1.18mg％ at one year stored sample. A general trend in change of color was almost white immediatly after brewing but a increase in Hunter "b" value and "a" value were observed depending on brewing time prolonged. Taste and overall palatability of Ewhaju after 100 days of brewing were significantly superior(p<0.05, p<0.01).

• The Korean Journal of Food And Nutrition
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• v.30 no.5
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• pp.916-922
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• 2017

This study was conducted to investigate changes in organoleptic properties and taste components including free sugar, organic acid and free amino acid with addition of walnut. Changes in total nitrogen were insignificantly different with addition of walnut. Amino type nitrogen content was decreased in proportion to supplemental level of walnut. Content of organic acids, of which three kinds were detected, such as citric acid, malic acid and lactic acid increased more than two times with addition of walnut. Contents of free sugar and amino acid were decreased with addition of walnut. The proportion of essential amino acid was 40.6~41.4 percent. Glutamic acid in total amino acid was increased in proportion with addition of walnut. The highest sensory evaluation score was recorded in soy sauce with addition of 2 percent walnut. Together, it was expected that 2 percent addition of walnut to soy sauce has a positive effect on the taste of soy sauce.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.39 no.5
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• pp.502-511
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• 1994

Investigated were the relationships between plumule elongation characteristics and seedling emergence of 98 varieties including native, improved and red rice varieties of Korea, and varieties from U.S.A., Italy, Japan, etc. under proper and excess soil moisture regimes. Under excess soil moisture condition the seedling emergence and establishment rates were much lower in most of the varieties and the seedling emergence rates were delayed substantially in all varieties employed. The seedling emergence rates were lowest in dwarf and some semi-dwarf varieties showing poor plumule elongation under proper soil moisture condition. The seedling emergence and establishment rates were significantly correlated with the length of mesocotyl, coleoptile and incomplete leaf under both soil moisture regimes, and with the lower first and second internode length under excess soil moisture condition. Average emergence duration showed significant negative correlation with the length of mesocotyl, coleoptile and incomplete leaf under both soil moisture regimes and significant positive correlations with the first and third lower internode length. Based on the standardized partial regression analysis only the variations of mesocotyl and coleoptile length contributed significantly to the varietal difference in seedling establishment rate, and so did the variations of mesocotyl and incomplete leaf length to the varietal differences in emergence speed. In conclusion varieties with greater elongation characteristics of mesocotyl, coleoptile and incomplete leaf are desirable for higher and speedy seedling establishment in dry-direct seeding.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.9
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• pp.1333-1338
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• 2015

This study investigated the effects of addition of Chrysanthemum indicum L. extracts on quality characteristics of Kukhwju during fermentation. Fermented liquors without C. indicum L. were used as the control group. For experimental groups, we added 1, 2, 5, and 10% C. indicum L. extracts and brewed according to the addition method written in Yorok. The pH level during fermentation phase, alcohol concentration, level of reducing sugars, and acidity were measured in each of the experimental groups. After fermentation, we measured total contents of phenols, antioxidant effects, free sugars, organic acids, and chromaticity. During fermentation, no significant difference was observed between the C. indicum L. group and control group. Regarding total phenol contents and antioxidant effects, only the 5% and 10% C. indicum L. groups showed higher contents of phenols than the non-addition group. In general, 5% and 10% C. indicum L. addition groups were positively evaluated. In conclusion, Kukhwaju with 10% C. indicum L. extract showed the best antioxidant effects. In the present study, we obtained different characteristics and determined the optimum addition amount of C. indicum L.