• Applied Biological Chemistry
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• v.8
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• pp.45-50
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• 1967

Starch was liquefied by the bacteriological ${\alpha}-amylase$ and saccharified separately by four strains of mold as saccharogenic enzymes, then thise was fermented for research the fermentation rates, the usefulness of application of four strains of mold and the S.P to need in proportion increasing of concentration of mixed-starches for brewing in this experiment. The obtained results were as follows: 1) In the ability of saccharificatien, fermentation and acid resistance, Aspergillus usamii mut shirousamii, which were used to produce the koji, were excellent, however, Rhizopus delemar had heavy pollution in a lot of production of koji, were-as its qualities as enzyme was good. 2) The necessary S.P in proportion to the concentration of mixed-starch for brewing was found in this experiment in which was fermented in the various concentration of the adding S.P and the mixed-starches for brewing. 3) In the experiment of almost manufacture scale, the S.P needed essentially in the saccharogenic formentation was found and the usefulness of the necessary S.P was observed, and in fact in the manufacture scale it was safer to add the S.P more than 1.2% because it must be considered that the ability of enzymes is reduced by heat or acid. 4) The period of fermentation was shorten because the conditions for yeast propagation were excellent as a results of starches being liquefied by bacteriological amylase, and saccharified by molds as saccharogenic enzymes.

• 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.

• Microbiology and Biotechnology Letters
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• v.44 no.3
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• pp.229-235
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• 2016

Korea has a long history of brewing traditional rice wine using a authentic starter culture called nuruk, which contains natural microbial flora. Because rice wine is consumed fresh without filtration, its viable cells contribute to the biological activities of the wine. In numerous studies, microbial strains isolated from rice wine have been screened for their functionalities, which were mainly probiotic properties and antimicrobial activities. Indeed, some lactic acid bacteria (LAB) were confirmed to have strong probiotic activities as well as other health-promoting effects. Moreover, some of the isolated probiotic strains produced functional compounds, such as exopolysaccharides and γ-aminobutyric acid. For antimicrobial activities, some LAB and yeast strains were identified to produce bacteriocins and killer toxins, respectively, with significantly broad spectrum of antimicrobial activity. These functional strains originating from traditional rice wine and their metabolites can be used directly for the production of value-added food products.

• Journal of the Korean Society of Food Culture
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• v.16 no.4
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• pp.371-377
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• 2001

Li was a sweet beverage containing $2{\sim}3$ percents ethyl alcohol made from malt by spontaneous fermentation from ancient custom to fifteenth century. Li was changed to the rice wine being a sweet beverage of low alcohol content using nuruk as starter and the sikhae which is non-alcoholic fermented beverage. Li was made for drinking and ceremony in Korea, China and Japan. It disappeared from the beverage items along with its method of manufacture from malt, but in Korean had made Li using nuruk until recent. We made Li according to Book of Imwon-Keongjae Ji (The book of country economy) methods for reappearance of Li. Fermentation characteristics for the production of Li with Saccharomyces cerevisiae, Saccharomyces bayanus and Saccharomyces sake were investigated. Among the yeast strains tested, Li fermented with S. sake showed higher alcohol production. Total sugar decreased considerably during the whole period of fermentation(30 hours), while ethyl alcohol content increased at $2.98{\sim}3.52%$. As the fermentation progressed, the pH decreased until the 30 hours of fermentation, while total acid increased during the same period. In fermentation of 36 hours, Li consisted of about $2.98{\sim}3.52%$ of alcohol content, $5.3{\sim}6.0%$ of total sugar, $1.45{\sim}2.21mg%$ of reducing sugar and total acidity were reached up to $24.4{\sim}29.5mg%$ for Li manufactured with S. cerevisiea sake, S. bayanus and S. sake.

• The Journal of the Convergence on Culture Technology
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• v.6 no.4
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• pp.739-745
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• 2020

Makgeolli is a liquor that represents Korea and is made by mixing yeast and water with starch. Physicochemical Characteristics and Antioxidant activities of rice, nuruk, water and Fermentation time different to Makgeolli. Alcohol content was 6.76~14.56%, Reducing sugar content 1.17~1.68g/L and M5~M6 samples was higher 1.68g/L~2.43g/L. M1~M9 samples pH 3.56±0.02 and total acid 0.45~0.83%. Makgeolli total phenol content was average 966.38mg/L and ABTS 0.77mM. The Antioxidant activity measurements of FRAP and ABTS showed a similar correlation with the total phenol content. Makgeolli showed a high correlation cofficient of r GAE / PRequiv=0.8582 and r GAE / TEAC=0.9769. We intend to make rice, yeast, brewing water, fermentation period, etc. different conditions of makgeolli and analyze the status of fermentation progress and use it as basic data of quality indicators of the fermented rice wine process.

• The Korean Journal of Food And Nutrition
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• v.36 no.6
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• pp.425-435
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• 2023

This study investigated quality characteristics and functionality of rose sparkling wine that were manufactured by secondary fermentation after inoculation of yeast strains. The pH of the samples ranged from 3.96 to 4.05 and total acidity ranged from 0.23 to 0.32%. The alcohol contents of wines ranged from 6.4 to 6.6% and the CO₂ pressure ranged from 2.0 to 2.6 bar. The brightness of rose wines ranged from 84.72 to 87.36, the redness from 9.28 to 14.15, and the yellowness from 9.50 to 19.20. The hue value of wines ranged from 1.137 to 1.513 and color intensity ranged from 0.724 to 0.882. Aroma analysis identified 14 alcohols, 22 esters, 4 ketones, 4 acids, and 17 miscellaneous compounds. The total tannin contents and total polyphenol contents of wines were 11.28~12.43 mg% and 24.79~28.20 mg%, respectively. The DPPH radical scavenging activity of wines ranged 63.33 to 67.89% and the ABTS radical scavenging activity of wines 82.16~86.06%. The results of this study provide a basis for establishing the brewing process of rose sparkling wines yeast strains.

• Microbiology and Biotechnology Letters
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• v.29 no.4
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• pp.212-220
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• 2001

Rare mating was used to select a respiratory deficient mutant of Saccharomyces cerevisiae HDC52 strain. Glucoamylase gene of S. diastaticus K114 was developed into the RD mutant which could uptake maximum amount of non-fermentable sugars through the expression of glu- coamplyase gene and the fermentation characteristics of the developed strain HCS were investigated. The size of HCS yeast and HBD52 yeast strain were 13 $\mu\textrm{m}$ and 10$\mu\textrm{m}$ respectively. HCS strain which can uptake maximum amount of non-fermentable sugar through the expression of glucoamylase gene was developed. By karyotype anal- ysis. HCS stain but not RD mutant HBC52 showed a band of 1150 kb chromosome DNA This band should include glcoamylase gene from Saccharomyces diataticus K114 THis strain has glucoamylase which can degrade starch By transduction and contrnuance of glucoamylase gene HCS strain gegraded strach and formed halo. Also, HCS strain maintained the character after 50 generations. Glucoamylase activities of Saccharomyces diastaticus K114 and HCS yeast strains are 9.5 and 2.7~3.4(unit/ml) HCS and HBC52 strain showed similar sugar fermentation patterns and low flocculation In spore and film forming test, HCS and HBC52 strain formed neither spores nor films. In the limit fermentation test, HBC52 strain showed fermentation level of 68% and HCS strain showed 76~78% As the limit attenuation of HBC52 and HCS were ($2.00^{\circ}$P) and ($0.7~0.93^{\circ}$P) This study demon- strates and HCS strain may be used for low carbohydrate beer fermentation.

• Korean Journal of Food Science and Technology
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• v.49 no.4
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• pp.383-389
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• 2017

This study aimed to select a yeast strain for optimizing the quality of distilled spirits. The brewing and distilling properties of 4 KFRI (Korea Food Research Institute) yeasts (Y88-4, Y98-4, Y172-6, Y192-4) and 2 industry yeasts (C1, C2) were compared. For investigating the possibility of using these strains on an industrial scale, diverse analytical methods were applied to assess parameters associated with distilled spirit quality such as alcohol content, pH, total acidity, and soluble solid content. After 11 days of fermentation, the alcohol strength obtained using six yeast strains reached 13.9-16.4% (v/v), while pH was 3.9-4.0, and total acid was 0.40-0.52%. To compare GC-MSD Volatile flavor components, all the distilled spirit samples were diluted to 20% (v/v) alcohol strength. Seven fusel alcohols, 26 esters, 2 acids, and 3 miscellaneous compounds were detected in the distilled spirits. Y88-4 had the most abundant volatile flavor component and scored the highest overall preference in sensory evaluation. After analyzing the various properties of yeasts, strain Y88-4 was finally selected as the best strain for producing distilled spirits.

• The Korean Journal of Mycology
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• v.10 no.2
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• pp.75-83
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• 1982

As a primary study for cell growth and alcohol production of a cider yeast, Saccharomyces sp. R-11, cultural and nutritional characteristics of the strain were investigated. The results obtained were as follows: The optimum culture medium for this strain was a synthetic medium, Henneberg B, and sucrose was the best carbon source for yeast growth and alcohol production. Optimum sugar concentrations for yeast growth and alcohol production were 15% and 25%, respectively. Optimum pH and temperature of the basal medium for growth of this strain were 4.5 and $30^{\circ}C$ respectively. The yeast growth was enhanced by the addition of 100 ppm of $Mg^{2+}$, but significantly inhibited by the addition of 100 ppm of $Co^{2+}$. Lower temperature and maintenance of optimum pH for yeast growth increased the final alcohol concentration. Under optimum condition for cell growth at stationary culture, generation time and specific growth rate of the strain were 7.5 hr and 0.092 $hr^{-1}$, respectively. At 8% initial alcohol concentration, yeast growth was inhibited about 50% and this strain could not be grown at more than 12% initial alcohol. The strain could be grown at less than 125ppm $SO_2$without alcohol addition, and at less than 75 ppm $SO_2$ with 8% initial alcohol. The higher sulfur dioxide concentration of a medium, the longer lag phase in yeast growth was observed. This strain could induced alcoholic fermentation at less than 10% initial alcohol concentration with 0 and 25 ppm $SO_2$, at less than 8% initial alcohol with 50 and 75 ppm $SO_2$, and at less than 6% initial alcohol with 100 and 125 ppm $SO_2$.

• Food Science and Preservation
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• v.8 no.3
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• pp.320-325
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• 2001

In fermentation characteristics, R2 was suitable for fast start and fermentation, while UCD530 was tool suitable far complete fermentation at 25$^{\circ}C$. T73 and AC- strains produced much more total acid compared to other strains and it was concerned with producing large amount of succinic acid and acetic acid. OC-2, UCD530, Beaujolais, and BC strains revealed low fermentation efficiency (below 62.0%), but EC1118, RC212, T73 and BM45 strains showed opposit result (above 70.0%). D254 and Wadenswil 27 seemed to have excellent cohesive ability because these two yeast strains made somewhat hard precipitation at the bottom after complete fermentation. T73 and CEG gave higher amounts of acetic acid (above 630 mg/L), while UCD530, W-3 and Beaujolais recorded low concentration (below 200 mg/L). In sulfur dioxide tolerance, preferable culturing temperature and times were 25$^{\circ}C$ and 72 hr respectively. The strains R2, BM45 and L2056 revealed high sulfur dioxide tolerance (above 30mg/L), white 71B, Wadenswil 27 and Beaujolais showed the opposite result (below 5mg/L)