• Microbiology and Biotechnology Letters
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• v.3 no.1
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• pp.41-48
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• 1975

The chemical components and quality of Takjoo mash were examined on the product brewed by the case of commercial amylase, Lactobacillus bulgaricus and the yeast. 1. Lactic acid was produced at the range of 917~1,350 mg per 100 ml of the mash brewed using wheat flour, corn flour, rice and pressed barley, while succinic acid was formed at the range of 6~32 mg per 100m1 of the mash. 2. Citric acid was formed at the concentration of 6.5mg per 100m1 of the mash on the use of pressed barley, and malic acid formed at the concentration of 1.7 mg and 1.4 mg per 100m1 of the mash respectively, on the use of wheat flour and corn flour. 3. No remarkable differences between the kind of raw materials and commercial amylases and compared with the mash brewed with Nurook were observed in the components of fusel oil formed in the mash. 4. Seventeen kinds of the amino acids of the mash brewed with commercial amylase, Lactobacillus and the yeast were detected and its content was 31mg per 100ml, which is less than that of the conventional takjoo, but the contents of glycine and alanine which pray as the component of seasoning in takjoo were sufficient.

• Korean Journal of Food Science and Technology
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• v.33 no.5
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• pp.589-595
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• 2001

Effect of anti-microbial agents, such as alcohol, garlic, chitosan, K-sorbate, or mustard, or pasteurization on the quality of traditional kochujang was investigated during storage at $30^{\circ}C$ for 24 weeks. Water activities of kochujang decreased after 12 weeks of storage. Consistency increased during storage and highest consistency of kochujang was obtained by the addition of mustard or garlic. Hunter a- and b-values decreased linearly as storage time passed. The degree of increase in total color difference$({\Delta}E)$ of alcohol added group was the highest among the tested anti-microbial agents. Gas was rapidly produced in the control and chitosan added group of kochujang. Capsanthin content decreased more rapidly in the group of alcohol, garlic or mustard added kochujang than the other group. Viable cell counts of yeast and aerobic bacteria in kochujang increased up to 12 weeks of storage, and then decreased slowly. The number of yeast was low in K-sorbate or alcohol added group. Activity of ${\alpha}-amylase$ decreased during storage, but that of ${\beta}-amylase$ increased in alcohol, garlic, K-sorbate added or pasteurized kochujang. Protease activities did not show any remarkable differences in the groups of tested during storage.

• The Korean Journal of Food And Nutrition
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• v.28 no.1
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• pp.104-110
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• 2015

This study was performed to investigate the changes in quality characteristics of Takju under different storage temperatures (5, 10 and $20^{\circ}C$) and length of shelf life. Under all storage conditions, alcohol content, pH, total bacteria and yeast counts of Takju decreased with increasing storage period. However, aldehyde content and total acidity increased. In sensory evaluation, flavor, taste and overall satisfaction of Takju under all storage conditions decreased with increasing storage period and temperature. Quality characteristics such as alcohol content, total bacteria count, yeast count, total acidity, pH, aldehyde content and overall satisfaction at high storage temperature changed faster than low storage temperature. Alcohol content, total bacteria count, yeast count, total acidity, pH and aldehyde content had high correlations among factors affecting sensory characteristics (p<0.01). based on the results from this study, expected expiration dates of Takju are 55, 26 and 3 days at 5, 10 and $20^{\circ}C$, respectively.

• Applied Biological Chemistry
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• v.39 no.1
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• pp.1-8
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• 1996

A one-stage, continuous-flow bioreactor with both immobilized and suspended cells was used to investigate the roles of lipid supplements in ethanol production by Saccharomyces cerevisiae. The reactor performance and the level of alcohol dehydrogenase(ADH) activities of the suspended cells, grown under various conditions, were measured. When ergosterol and/or oleic acid were added with surfactants to the yeast culture grown under non-aerated conditions, remarkable increases in ethanol production and cell growth was achieved, but specific ADH activities were not affected. Especially, no difference of specific ADH activities of the suspended cells grown under aerated and non-aerated condition was observed. The addition of the surfactant as a supplement also resulted in significant increases in ethanol production, cell growth, and specific ADH activity. When ergosterol and oleic acid were added to the yeast culture exposed to higher ethanol concentration($>40\;g/{\ell}$) level, ethanol production, cell growth, and specific ADH activity were increased, but the addition of surfactant was as effective as at lower ethanol concentration level. The results indicated that lipid supplements were more effective at higher ethanol concentration level than at lower ethanol concentration level during ethanol production. ADH isozyme patterns of the yeast cultures grown under various conditions on starch gel electrophoresis showed only one major band, probably ADH I. The migrating distance of the major isozyme, however, varied slightly according to the culture conditions of the cells. No apparent correlation was found between specific ADH activity and amount of ethanol produced. Cell mass was more important factor for ethanol production than specific ADH activity of the cells.

• The Korean Journal of Mycology
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• v.41 no.3
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• pp.167-171
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• 2013

The goal of this study was to screen a useful alcohol fermentative yeast for Gugija leaf makgeolli (Gl makgeolli) brewing and establish its optimal fermentation condition. Gugija leaves with various alcohol fermentative yeasts were added into the mixture of cooked non-glutinous rice and koji, and then fermented at $25^{\circ}C$ for 7 days. Among several Gl makgeolli, ethanol contents was the highest in Gl makgeolli made by S. cerevisiae F-1. Therefore, we selected S. cerevisiae F-1 as suitable yeast for brewing of Gl makgeolli. Gl makgelli with the best total acceptability and high antihypertensive action was obtained when cooked non-glutinous rice (120 g), boiled D.W (100 mL) and JJ koji (60.5 g/300 sp) were mixed and fermented for 2 days at $30^{\circ}C$ with S. cerevisiae F-1 (5%), and added again cooked non-glutinous rice (150 g), glutinous rice (100 g), D.W (500 mL) and Gugija leave (0.1%/cooked rice) and further fermented for 5 days at $25^{\circ}C$.

• Food Science and Preservation
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• v.6 no.4
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• pp.463-468
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• 1999

The characteristics and quality of Yakju with addition of ginseng powder originated in Choongchungdo were evaluated. At result, pH was decreased at the beginning stage of two stages fermentation and then slowly increased. Total acidity were increased in the cases of all (A), (B) and (C) during the fermentation. (A) group used Nuruk, crude enzyme and powder yeast showed the highest pH of 7.08 and total acidity of 0.84 at the 4th day of fermentation. The alcohol contents of B(21.0%) and C(20.4%) used cultured yeast were higher than A(19.0%) used powder yeast at the 4th day of fermentation. Also, inhibition against alcohol fermentation by ginseng powder wasn't showed and amino nitrogen contents were higher in (A) and (C) with addition of crude enzyme. Free sugar were the highest in (A) used both Nuruk and crude enzyme such as glucose of 599.16, maltose of 129.11mg%. Free amino acids were much more in A(580.02mg%) than in B(527.48mg%) and C(538.74mg%). from the sensory evaluation, desirable color and flavor qulity for 40 ages was (A) and (B) which was used Nuruk, and that for 20 ages was (C) which was used crude enzyme. However the best taste and overall preference was (B) for 20 and 40 ages of all. Therefore to produce high quality Yauju and commercialize, studies of fermentation process in Yakju should proceed later.

• Applied Biological Chemistry
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• v.27 no.1
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• pp.52-54
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• 1984

Ethanol fermentation from the chemically gelatinized starchy material was examined. The critical concentration of sodium hydroxide solution for gelatinization was dependent on the species of starch; 0.4M for potato and 0.6M for tapioca at room temperature. For alcohol fermention the starchy material was gelatinized by addition of sodium hydroxide solution, neutralized by sulfuric acid, and then yeast was added. The amount of $CO_2$ evolved during ethanol fermentation indicates that non-fermentable material was not produced from the starch by chemical gelatinization. In ethanol fermentation of potato and tapioca starch no significant difference was observed between the thermal and the chemical gelatinization.

• Journal of the Korean Society of Food Science and Nutrition
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• v.28 no.4
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• pp.794-800
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• 1999

This study was carried out to obtain the basic information for improving the flavor quality of yakju. Three kinds of yakju were prepared with different yeast strains to investigate the effects of those strains on flavor components. A total of 23 strains were isolated from fruits such as apple, pear, persimmon and citron and two strains were excellent in producing ethanol and flavors. They were identified as Saccharomyces cerevisiae S 2 and Saccharomyces cerevisiae S 6 from morphological cultural test and physiological quality. Yakju A, B and C were prepared with S 2, S 6 and Saccharomyces cerevisiae IFO 1950, respectively. Flavor components of yakju were analyzed by gas chromatography and mass spectr ometry. A total of 57 peaks were detected and 13 compound were identified. They were 4 alcohol, 2 esters, 7 acids and miscellaneous compounds.

• Proceedings of the Plant Resources Society of Korea Conference
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• v.18 no.1
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• pp.119-120
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• 2005

• Proceedings of the Korean Society for Applied Microbiology Conference
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• 1979.04a
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• pp.115.4-116
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• 1979

Acetone-dried cells of Arthrobacter simplex were entrapped in several preparations of hydrophilic urethane prepolymers and their steroid converting ability was examined. SeVeral solvents, such as methanol and propylone glycol, wereeffective for the conversion of hydrocortisone to prednisolone. The stability of the immobilized cells during storage and on repeated reactions was also examined. Thisconvenient entrapping method was also applicable for the immobilization of cellular organelles. yeast peroxisomes. The entrapped peroxi-somessh owed the activities of alcohol oxidase and catalase.