• Journal of the Korean Professional Engineers Association
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• v.21 no.2
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• pp.13-18
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• 1988

A Study for ethanol fermentation with immobilized yeast that is entrapped to Ca-alginate beads and batch system was carried out using molasses as substrate. The results are as follows. 1. The yield of alcohol fermentation is more efficacious then that of conventional fermentation process. The beads were used 15times and got a result of fermentation yield rate 89. 57％∼92.35％f, which is comparable with the rate of 86.3％ gained from the conventional fermentation process. 2. The concentration of Ca-alginate was 1∼5％ For long run use (2520 hours) it is necessary 2％ or more concentration of Ca-alginate. 3. The amount of the yeast cells for entrap to Ca-alginate beads was required 1.0g (indried material) or more for 200g Ca-alginate beads.

• YAKHAK HOEJI
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• v.3 no.1
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• pp.15-20
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• 1957

Resume 1. The toxic effect of $CuSO_4$ on the growth of yeast began in the 0.2mM and colony formation was completely inhibited in the 3mM $CuSO_4$ media. 2. The yeast strain which was trained sucessively from lower concentration media to higher one, could grow even in 10mM $CuSO_4$ media. 3. Rlb strain produced brown pigment in copper media. 4. Resistance of Rlb strain to $CuSO_4$ did not revert in non copper media. 5. The appearance of resistant strain was regarded as the result of "Mutation and Selection". 6. The alcohol fermentation ability of Rlb strain was lower than that of parent strain. 7. Rlb strain yielded some effective substance which induced the parent strain to resist against $CuSO_4$. 8. The dehydrogenase activity of yeast was inhibited by $CuSO_4$.

• Food Science and Biotechnology
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• v.14 no.5
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• pp.576-580
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• 2005

Ten yeast strains affecting doenjang flavor were isolated from soybean fermented foods (traditional meju and doenjang), among which Zygosaccharomyces sp. Y-2-5, showing excellent growth, glucose consumption, pH, and flavor production, was selected. Higher alcohols produced by Zygosaccharomyces sp. Y-2-5 related to flavor were 2-propanol, 1-propanol, 2-methyl-1-propanol, 1-butanol, and 3.3-dimethyl-2-butanol. Optimal culture conditions for Zygosaccharomyces sp. Y-2-5 were 10% (w/v) NaCl, pH 4.0, 3.0% (w/v) glucose concentration, and inoculation time day 0 or 15 doenjang fermentation.

• Journal of The Korean Society of Grassland and Forage Science
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• v.28 no.1
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• pp.49-60
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• 2008

A study was conducted to determine the effect of alcohol-fermented feedstuff formulated with byproducts on the fermentation characteristics and dry matter disappearance in the rumen. Dietary treatments were either a soybean curd-based alcohol-fermented feedstuff(AFS) and brewery grain-based alcohol-fermented feedstuff(AFB). The AFS and AFB are composed of 50% commercial beef cattle feed, 50% soybean curd dreg, 5% molasses and 0.5% yeast, and 25% commercial beef cattle feed, 25% brewery grain, 25% soybean curd dreg, 25% corn grit, 5% molasses and 0.5% yeast, respectively. The ruminally cannualted Korean cattle were utilized to investigate the change of ammonia, pH alcohol, volatile fatty acids, and DM digestibility at 0, 2, 4, 8 and 12 hr after feeding. The rumen ammonia concentrations were significantly lower in AFS and AFB with incubation time, especially at 6 hr incubation(AFS, 0.7 mg/dl; AFB, 1.5 mg/dl; control 2.5 mg/dl). Lower rumen pH was observed in AFS and AFB during the early stage of incubation, but no significant difference was found at late stage of incubation. The total VFA concentrations were not affected by diet treatments at 2 hr incubation time, but the concentration significantly decreased after that. The dry matter disappearance was significantly lower in AFS and AFB during the early stage of incubation. However, the dry matter disappearance of AFS and AFB was similar to that of control during the late stage of incubation. It is concluded that the industrial byproducts such as soybean curd dreg and brewery grain were effective materials to make an alcohol fermented feedstuffs and resulted in better fermentation characteristics in the rumen when both were applied to Hanwoo.

• Applied Biological Chemistry
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• v.16 no.1
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• pp.1-11
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• 1973

In order to obtain the basic informations on the production of single cell protein from ethanol, 145 yeast strains utilizing ethanol as a sole carbon source were isolated from 32 soil samples in Korea. A yeast strain showing the highest cell yield among the isolated strains was selected and identified. The optimum culture condition, utilization of other carbon sources and the cultural characteristics for the selected yeast, and the chemical analysis of the yeast cell composition, and utilization of ethanol by the selected yeast were investigated. All the culture was carried out in the shaking flasks. The results obtained were as follows: 1. The selected yeast strain was identified as Debaryomyces nicotianae-SNU 72. 2. The optimum composition of the medium for the selected yeast is : Ethanol 40 ml, Urea 0.5 g, Potassium phosphate (dibasic) 0.5 g, Ammoium phosphate (monobasic) 0.15 g, Magnesium sulfate 0.05 g, Calcium chloride 0.01g, Yeast extract 0.005 g, Tap water 1000 ml. 3. The optimum pH was 5.0-5.5, the optimum temperature $30-33^{\circ}C$ and the aerobic state was unimportant. 4. Utilization of methanol, n-propanol, iso-propanol, n-butanol, iso-butanol, tert-amyl alcohol and acetic acid by the selected yeast was very weak. So substitution of the subtrate was thought to be impossible. 5. Studies on the propagation of the yeast cells showed that the lag phase of the yeast cells lasted 16 hours, and the logarithmic growth phase extended 16 to 28 hours. The specific growth rate was about $0.19\;hr^{-1}$ and the doubling time was 3.6 hours during the logarithmic growth phase. 6. As the result of the chemical analysis of the dry yeast cells, the content rate of the crude protein was 55.19 %, the content of others was similar to the average content of the yeast component. 7. After 34 hours cultivation, under the optimum culture condition investigated, the dry cell yield against the amount of the added ethanol was 53.4 % (W/V%), the dry cell yield against the amount of the utilized ethanol was 73.6 % (W/V%), the evaporation rate of ethanol was about 19.1 %.

• KSBB Journal
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• v.4 no.2
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• pp.167-171
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• 1989

The alcohol fermentation using glucose and lactose was carried out to study the effect of fermentation temperature on the ethanol tolerance of Saccharomyces cerevisiae STV89 and Kluyveromyces fragilis CBS397. The maximum specific growth rate and ethanol production rate were increased up to 35$^{\circ}C$ with the fermentation temperature, although maximum ethanol and cell concentration were decreased by increasing the fermentation temperature. The cell viability was also improved by lowering the fermentation temperature. Under the experimental conditions, the best ethanol tolerance of yeast strains was obtain at $25^{\circ}C$. The ethanol tolerance of S. cerevisiae is better than that of K. fragilis at the same fermentation condition. With respect to the carbon source, glucose is found to be more favorable for ethanol tolerance of K. fragilis than lactos.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.4
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• pp.592-601
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• 2015

Rubus coreanus is known as Korean black raspberry, native to Korea, Japan, and China. Preliminary studies evaluating their potential for cancer treatment in mammalian test systems are ongoing. In recent years, interest has been renewed due to their high levels of anthocyanins. Anthocyanins in black raspberry are important due to their potential health benefits as dietary antioxidant, anti-inflammatory compound, and as a chemopreventive agent. In the present study, Saccharomyces cerevisiae BA29 was isolated from black raspberry fruit and fruit juice as a biogenic amine non-producing strain for manufacturing of black raspberry wine, after which we investigated its characteristics: biogenic amine-producing ability, cell growth ability, alcohol-fermentation ability, and resistance to alcohol, glucose, and sulfur dioxide. Based on preliminary experiments, we optimized culture medium compositions for improving dried cell weight of S. cerevisiae BA29 by response surface methodology (RSM) as a statistical method. Design for RSM used a central composite design, and molasses with the industrial applicability was used as a carbon source. Through statistical analysis, we obtained optimum values as follows: molasses 200 g/L, peptone 30 g/L, and yeast extract 40 g/L. For the model verification, we confirmed about 3-fold improvement of dried cell weight from 6.39 to 20.9167 g/L compared to basal yeast peptone dextrose medium. Finally, we manufactured black raspberry wine using S. cerevisiae BA29 and produced alcohol of 20.33%. In conclusion, S. cerevisiae isolated from black raspberry fruit and juices has a great potential in the fermentation of black raspberry wine.

• Korean Journal of Food Science and Technology
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• v.32 no.5
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• pp.1168-1172
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• 2000

Fermentation characteristics for the production of honey wine with Saccharomyces sake, Saccharomyces bayanus and nuruk were investigated. Among the yeast strains and the mixture with nuruk tested, nuruk-Sacch. sake mixture and nuruk-Sacch. bayanus mixture showed higher alcohol production and better fermentability than the single strains. Total acid and pH did not change considerably during the whole period of fermentation. As the fermentation progressed, reducing sugar decreased rapidly until the 6 days of fermentation, while alcohol content increased rapidly during the same period. In fermentation of 6 days, honey wine consisted of about $7.5{\sim}8.1^{\circ}Brix$ of soluble solid, $22.7{\sim}31.8%$ of reducing sugar. Alcohol content were reached up to 12.5 and 13.1% for honey wine manufactured with nuruk-Sacch. sake mixture and nuruk-Sacch. bayanus mixture, respectively, relative to $5.2{\sim}7.2%$ of the single strains. Generally, honey wines prepared with the mixture of nuruk-yeast strains were fermented more efficiently than those with the single yeast.

• Journal of the Korean Society of Food Science and Nutrition
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• v.11 no.2
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• pp.31-35
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• 1982

Alcohol fermentation was carried out by using the yeast (S. cerevisiae) and soybean whey as the sole carbon source. The whey was gained form waste after manufacturing of soybean curd. The whey contained approximately one gram sugar per hundred mililter and the sugar was consisted of a 65 per cent of reducing sugar. However, it showed a low protein content of 43mg per the same volume. Ammonium sulfate showed the best effect on the generation of carbon dioxide among three kinds of tested nitrogen sourogen sources, potassium nitrate, urea and ammonium sulfate. Thus, fermentation was carried out with supplement of 2.0g ammonium sulfate to one liter of soybean whey. During fermentation continued for 48 hours, the maximum amount of ethanol 1.86g was produced from one liter of soybean whey. The ethanol fermentation utilized 81 and 94% of its initial sugar and protein contents, respectively.

• KSBB Journal
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• v.6 no.1
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• pp.85-90
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• 1991

Experiments of alcohol fermentation of the yeast,K. fragi1is CBS 1555 were performed to obtain the following results. In these experiments, the initial concentrations of sugar which was composed of inulin and fructose as weight ratio of one to one were 30, 50, 75, 100 and 150g/l and the initial densities of the microorganism were less than 0.5g/l, 10g/1 to 15g/1, and 50g/l. The functional relationship among specific growthrates, sugar concentrations, and alcohol concentrations could be expressed by Aiba-shoda equation and the specific growth rate represented the trend that decreased with increase in the initial concentration of the microorganism. Also, $\mu$max and Ks of Monod's equation could be expressed as the function of initial cell concentration like the following equations. $\mu$max=0.8-0.008X Ks=0.54X+8 In the region that sugar, alcohol and cell concentrations were 10g/1 to 120g/l, 0g/l to 60g/l and 0.5g/l to 50g/l respectively, the differences between the experimental values and the calculated ones for specific growth rate approached to 40% with respect to experimental values at the worst cases, but in most cases, those were distributed in the range of less than 20%.