• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.8
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• pp.5468-5475
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• 2015

This present work was aimed to analyse characteristics of fermentation and aging of Korean traditional cheongju prepared by adding of different brewing water. The three different mashes were used for fermentation and maturation. The cheongju(A) was prepared without adding of brewing water in two stage mashing. Cheongju(B) and cheongju(C) were made with adding of 1 liter and 2 liter brewing water in two stage mashing respectively whereas the cheongju(B) and cheongju(C) showed higher fermentation ability than that of cheongju(A) regarding to pH, ethanol, specific gravity and sugar concentration(brix). In terms of volatile compounds content after six months aging, cheongju(A and B) prepared by adding brewing water showed the higher content of ethyl acetate than that of cheong(C) and the concentrations were maintained during the aging period. In addition, the content of fusel oil(n-propanol, i-butanol, n-butanol, i-bmyl alcohol, n-bmyl alcohol)indicated similar pattern as ethyl acetate. The organic acid of cheongju B(4873.46 mg/l) and C(4963.12 mg/l) also indicated the higher content than that of cheongju A(4661.47 mg/l). In conclusion, cheongju B and C prepared by adding brewing water in two stage mashing showed better quality and taste than that of cheongju A.

• Applied Biological Chemistry
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• v.45 no.3
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• pp.138-144
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• 2002

In order to improve the quality of foxtail millet wine, zymological properties by isolated strains from Nuruk were investigated. Saccharomyces sp Y5-1 as brewing yeast, Aspergillus sp. M6-3, Aspergillus awamori 6970, and Aspengillus usamii mut. shirousamii 6959 (KCTC) as saccharifying molds were used, respectively. Acid content, soluble solids, color (b) and alcohol contents were increased during fermentation. Ethanol concentration of millet wine made with Nuruk by Aspergillus awamori 6970 and Aspergillus usamii mut. shirousamii 6959 were higher than the other, 10.6 and 10.1% respectively. Citric acid was only detected on $1{\sim}2$ day starting fermentation. Oxalic acid, lactic acid and acetic acid of millet wine were high in the wine made of Nuruk by Aspergillus usamii mot. shirousamii 6959, Aspergillus awamori 6970 and traditional Nuruk, respectively. During fermentation, glucose and xylose was higher than the others. Xylose was increased, but most of other sugar were decreased during fermentation. Acetone, ethyl acetate, methanol, ethanol, n-propanol, iso-buthanol and iso-amyl alcohol were detected In the wine made with Nuruk by Aspergillus awamori and Aspergillus usamii mut. shirousamii, iso-imyl alcohol and ethanol were high. On sensory evaluation, the wine made with Nuruk by Aspergillus usamii mut. shirousamii was the best on color and taste.

• Journal of the Korean Society of Food Science and Nutrition
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• v.32 no.8
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• pp.1206-1213
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• 2003

In order to use nutraceutical components in Yulmoo (Coix lachryma-jobi L. var. ma-yuen Stapf), the acceptability of Yulmoo for Takju (Korean rice wine) was examined in terms of the production of volatile components. When Yulmoo was added to the Takju made by commercial koji as a substitute of starch at 0 (rice 100%), 15, 30, 60, and 100%, the ethanol content slightly increased to 13.6, 15.2, 15.2, 14.1, and 13.8%, the Production of isobutanol and iso-imyl alcohol increased as the amount of Yulmoo increased. While the use of Yulmoo to the Takju as the nuruk (Korean traditional koji), inoculated with Aspergillus kawachii (AK) and Rhizopu japonicus (RJ), decreased the contents of n-propanol, iso-butanol, and iso-amyl alcohol as well as the contents of ethanol from 14.3% to 11.2 [AK], 7.5 [RJ], and 10.4% [AK + RJ]. The Yulmoo nuruk in Takju increased the production of acetaldehyde and ethyl acetate indicating the negative effect in the organoleptic evaluation. It was determined that the addition of Yulmoo as a starch source or as nuruk has a critical effect on the production of fusel oils and other volatile compounds in Takju fermentation.

• Culinary science and hospitality research
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• v.21 no.1
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• pp.267-280
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• 2015

This study was carried out to evaluate the quality characteristics of Takju, Yakju, Spirit made by various cereal Nuruks which were made by Jokuk(whole wheat), Bunkuk(wheat flour), Maekkuk(whole barley). pH, Brix, cell number of yeast, alcohol content, flavors, organic acid, and sensory evaluation of brews were employed to analyze current study. Results showed that pH value of brews during fermentation decreased, while Brix value increased. In addition, alcohol contents increased up to 11 day's fermentation, but there were no significant differences among Jokuk, Bunkuk and Maekkuk(p<0.05). Cell numbers of yeast dramatically increased up to 5 day's fermentation, and then decreased. After 13 day's fermentation cell numbers of yeast were similar among Jokuk, Bunkuk and Maekkuk. In terms of analysis of flavor components, acetone and n-amyl alcohol were not detected in all brews, however fusel oil level was 494.65 mg/L in Maekkuk, and 525.4 mg/L in Bunkuk. Lactic acid showed the highest level in organic acid analysis. Furthermore, Jokuk and Maekkuk showed highest score in Takju, Maekkuk showed highest score in Yakju in sensory evaluation, although Jokuk, Bunkuk, and Maekkuk revealed similar score in spirit.

• Applied Biological Chemistry
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• v.22 no.2
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• pp.97-100
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• 1979

Tea leaves were harvested from the two cultivating sites in May, July and September. Tannin and caffeine, main factors for the quality of tea products, were analyzed and compared with the wild tea leaves and the cultivated. Aroma components of two varieties of tea leaves harvested in September were analyzed by gas-chromatographic method. The results obtained were as follows. 1. Tannin contents were 10-14% same as Chinese tea variety and increased gradually to September and showed no difference between the wild tea leaves and the cultivated. 2. Caffeine contents were 1.5-3% same as other Chinese variety and showed no difference between the wild tea leaves and the cultivated. 3. Aroma components showed nearly similar patterns between two different tea varieties and were identified as phenol, iso-butyl aldehyde, n-butyl aldehyde, iso-valer aldehyde, n-butyl alcohol, iso-amyl alcohol, iso-valeic acid, benzaldehyde, n-valeric acid and linalool among 32 peaks.

• Journal of the East Asian Society of Dietary Life
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• v.1 no.1
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• pp.99-111
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• 1991

In each nuruk using today, effect of pH on glucoamylase activity and viable cell count of yeast and bacteria was measured. Common components during fermentation, alcohol, acetaldehyde and acetone, amino acid composition, and total sugars and mineral content were determined in yakju(korean wine) brewed from different ingredients and by different methods. Results are summarized as follows ; 1. The lower the pH, the lower the glucoamylase activity in JK, BK, JK-S BK-S and JN. But the higher the glucoamylase activity ratio in Koji and KN. 2. Yeast and bacteria cell count could not determined in nuruk inoculated of seed. In JK, BK and JN, yeast cell count was 50${\times}$104∼80${\times}$104, bacteria cell count was 5${\times}$106∼24${\times}$106. 3. In yakju during fermentation, pH was higher in RU, total acidity content was higher in ST-N, ST-K, RU and ST-RUPO and alcohol content was lower in RUPO and ST-RUPO. 4. Ethanol and acetaldehyde content were highest in dukyunju. Trace amount of acetone was determined only in ST-K, RUPO and ST-RUPO . n-Propyl alcohol content was higher in ST-K, ST-RUPO and ST-N, iso-butyl alcohol content was higher in L-RUPO, Dukyunju and Songyupju and iso-amyl alcohol content was higher in Songyupju, RU, L-RUPO and Dukyunju. 5. In amino acids composition of each yakju, Pro, Ala and Val content was higher than other amino acids. Total amino acids content was the highest in Dukyunju and second highest in ST-N, NH3 was higher in ST-N, Dukyunju, RUPO than other samples. 6. Total sugars content was the highest in ST-N and second highest in RU. 7. P, K and Mg content were higher in Dukyunju and ST-N than in other samples. In Dukyunju, Ca and P ratio was 0.075 because of low Ca content and high P content.

• Journal of the Korean Society of Food Science and Nutrition
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• v.31 no.4
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• pp.578-582
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• 2002

This study was conducted to determine whether pectinase treatment would affect the process of alcohol fer-mentation with persimmon. The pectinase did not change pH and total acidity throughout the alcohol fermentation. However, the concentrations of reducing sugar were significantly lowered with the fermentation time, compared with controls. During the alcohol fermertation, the concentration of reducing sugar decreased rapidly up to 60 hours, unchanged from 60 to 72 hours, and then increased thereafter. The total alcohol concentrations of pectinase-treated groups were significantly higher than that of alcohol fermentation containing without pectinase. Among concentration 200 and 500 ppm had the most pronounced increase in the yield (%) of total alcohol (96%, respectively) and then, 300, 400 ppm and control in descending order. The contents of 5 major alcohols (acetaldehyde, methanol, n-propy alcohol, iso-butyl alcohol and iso-amyl alcohol) were measured. Among alcohol constituents, acetaldehyde and methanol were detected to be the lowest at control and methanol the highest at 200 ppm. These observations indicated that pectinase treatment would increase the yield of total alcohol, whereas it also raised methanol production during persimmon alcohol fermentation.

• Analytical Science and Technology
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• v.17 no.1
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• pp.23-28
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• 2004

Trace amount of uranyl (II) has been determined spectrophotometrically by measuring the optical density of the light blue yellowish coloured solutions formed by reaction between the metal ion and nicotinohydroxamic acid (NHx) in presence of different secondary ligands in strong isoamyl alcohol alkaline medium. The absorption maxima for both aqueous and extracted systems measured at their respective optimum pH were found to be 360 and 559 nm (DETA), 375 and 358 nm (EDA), 369 and 362 nm (piperidine), 354 and 341 nm (pyridine) and 363 and 336 nm (3 piperidine), 354 and 341 nm (pyridine) and 363 and 336 nm (3 - picoline), respectively at which Beer's law was obeyed. Effect of pH, reagent concentration, order of addition of reagent, time, temperature and solvent media on the absorption spectra have also been studied. Among the different systems studied, the shortest concentration range of uranyl(II) adhering to Beer's Law was 2.4 - 10.5 ppm observed for $UO_2(II)$ - NHx - DETA system in aqueous medium and also for iso amyl alcohol(IAA) extracted $UO_2$ - NHx - pyridine system was 2.4 - 7.8.

• Food Science and Preservation
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• v.6 no.1
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• pp.92-98
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• 1999

Contents of formed higher alcohols did not change about at 20 ppm of total nitrogen, but the contents were most at 200 ppm of total nitrogen especially in iso-amyl alcohol, and the contents showed decrease above at 400 ppm, greatly. Higher alcohols formation were high content at pH 4.0, but the contents were increase according to the condition of glucose and sucrose much. The formation of higher alcohols showed less in fermented condition of no elimination sample than in eliminated a mineral in each. Contents of higher alcohols were less in eliminated sample of biotine and inositol than in control, but the contents were higher than the others, and the contents showed especially high in eliminated nicotinic acid and thiamine. Higher alcohols formation were most at the content of SO\ulcorner in 20 ppm of them. The formation of higher alcohols showed more in Saccharomyces cerevisiae was form more in higher alcohols than Saccharomyces bayanus of two yeast strains.

• Journal of the Korean Society of Food Culture
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• v.11 no.4
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• pp.497-506
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• 1996

Fermentation characteristics and quality changes of the typical Korean traditional alcoholic beverages (Kwahaju, Sokokju, Baikhaju, Samhaeju and Hosanchun) were investigated during fermentation and after aging, respectively. They were prepared by their own brewing methods with respect to the same contents of rice and Nuruk (Korean-style bran koji). The consumed total sugar content of the alcoholic beverages (Sokokju, Baikhaju, Samhaeju and Hosanchun) which were brewed with the multiple input steps of seed mash and raw material (ABMIS) was higher than that of the alcoholic beverage (Kwahaju) which was brewed with the single input step (ABSIS). The pH values of all the beverages were similar and were ranged from 3.2 to 3.6. The acidity of ABMIS were lower than that of ABSIS, but alcohol concentration of ABMIS were higher. The fermentation period of the alcoholic beverages with triple input steps was the longest among them. The inner temperature and microbial growth in all the beverages increased at each of input steps of the raw materials. Fusel oil content of ABMIS was lower than that of ABSIS. Major components of the fusel oil were iso-amyl alcohol, iso-butanol, n-propanol, ethyl acetate and acetaldehyde, and its minor components were methanol and n-butanol. The results on quality changes of the alcoholic beverages after aging showed increase of alcohol in ABMIS, but decrease of sugar and acidity. Fusel oil contents of Kwahaju and Samhaeju decreased to be ranged from 3.1% to 13.9% after aging, but those of Sokokju, Baikhaju and Hosanchun increased to be ranged from 10.9% to 23.0%. Sensory evaluation of ABMIS showed better scores than that of ABSIS. It was suggested that the brewing method with multiple input steps of seed mash and raw material was one of the methods to increase fermentation efficiency for brewing the Korean traditional alcoholic beverages.