• Korean Journal of Food Science and Technology
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• v.38 no.5
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• pp.642-647
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• 2006

Yeast selection and the sterilization methods of strawberry juice were optimized for making strawberry wine. In addition, changes in the physicochemical characteristics of the wine during its fermentation were estimated. Maehyang and Yukbo cultivars of strawberry were tested for wine making; they contained 9.8 and 9.3% soluble solids and 0.59 and 0.58% titratable acidities, respectively. Among six yeasts tested, the Wg-15 and Sc-51 strains were selected based on the alcohol yield in the strawberry wine. Alcohol and soluble solid contents following heat treatment ($85^{\circ}C$, 10 min) or $K_2S_2O_5$ (200 ppm) treatment for sterilization were 7.10-7.20% and 5.60-5.80%, respectively, and no differences were observed between the Wg-15 and the Sc-51 strains. However, the flavor of wine produced following heat treatment was slightly better than that following $K_2S_2O_5$ treatment. The greatest amounts of alcohol were produced after 2 days of fermentation at $26^{\circ}C$. The alcohol content in wines produced with 12, 14, and 16% sugar content in the initial stages were 5.1, 6.0-6.2, and 7.5-7.7%, and the soluble solid contents were 3.9-4.3, 4.1-4.3, and 5.0-5.3%, respectively; no significant differences were observed between the Wg-15 and the Sc-51 yeast strains. For making strawberry wine, we proposed that the sugar content of Maehyang or Yukbo cultivars be adjusted to 16% soluble solids in the initial stages with heat treated at $85^{\circ}C$ for 10 min and fermentation with the Wg-15 or Sc-51 yeast strains at $26^{\circ}C$ for 8 days.

• Food Science and Preservation
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• v.20 no.5
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• pp.744-750
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• 2013

The indigenous Saccharomyces cerevisiae strains S13 and D8 were isolated at the microbial succession stage during spontaneous fermentation of Campbell Early wine as a resistant to potassium metabisulfite and a high sugar concentration. In this study, the fermentation characteristics of Campbell Early wine were investigated and compared with those of S. cerevisiae W-3, an industrial wine yeast. Alcohol production by the two strains was delayed at the initial fermentation stage, but increased fast when the fermentation continued. After the fermentation, the S13 and D8 wines contained 12.6% and 13.2% (v/v) alcohol, respectively, which were significantly higher than the alcohol content of the W-3 wine (12%, v/v). No marked differences were observed in the residual soluble solid content and the pH. However, the S13 and D8 wines showed high levels of total acid content, including malic and lactic acids. Especially, the lactic acid content was 8.9-fold in the S13 wine and six-fold in the D8 wine, compared with that of the W-3 wine. The two strains produced a higher level of acetaldehyde and a lower amount of methanol in the wine than the W-3 strain. The iso-Butanol content was lower in the two indigenous yeast wines with similar levels of n-propanol and iso-amyl alcohol contents than that in the W-3 wine. In the sensory evaluation, the S13 and D8 wines had higher scores for their color, flavor, taste and overall preferences than the W-3 wine. Especially, the S13 and D8 wines had much higher scores than the W-3 wine for flavor and color, respectively.

• Microbiology and Biotechnology Letters
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• v.39 no.1
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• pp.43-48
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• 2011

Physicochemical and organoleptic characteristics of Campbell Early red wines made by traditional method were investigated. The pH values of all Campbell Early red wines were ranged 3.0~3.3 during fermentation. The acidity value of Campbell Early red wine made by traditional method was 0.4~0.9%. Sucrose and alcohol contents were 6~7 Brix and 13.2~14.4% at the end of fermentation, respectively. Campbell Early red wine had the high sensory scores for color, aroma, taste, sharpness, after taste, and overall balance. Because Campbell Early red grapes are well fermented due to the rich fermentative sugar content, Campbell Early red wines made by adding EC-1118 yeast were shown to be the most appropriate.

• Culinary science and hospitality research
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• v.17 no.3
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• pp.162-171
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• 2011

This study investigates the physicochemical and organoleptic characteristics of Campbell Early white wines made by a traditional method. The pH values of all Campbell Early white wines were ranged from 3.2 to 3.5 during fermentation. The acidity value of the Campbell Early white wine made by the traditional method was 0.2~0.9%. Sucrose and alcohol contents were 6~7 Brix and 13.2~14.4% respectively at the end of fermentation. Campbell Early white wine had high sensory scores for color, aroma, taste, sharpness, after taste, and overall balance. Since Campbell Early grapes are well fermented due to their rich fermentative sugar content, Campbell Early white wines made by adding K1-V1116 yeast were shown to be the most appropriate.

• The Korean Journal of Food And Nutrition
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• v.33 no.5
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• pp.512-523
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• 2020

The objective of this study was to investigate the quality characteristics of Cheongsoo wine using freeze concentration fermented with 5 kinds of yeast strains (Saccharomyces cerevisiae EJ18, EJ30, HK22, HK32 and Fermivin). We compared the characteristics, volatile flavor component and physiological activity of 5 wines. The freeze concentration can increase the sugar concentration in grape juice by reducing its water content and the alcohol content of freeze-cententrated Cheongsoo wines ranged between 15.0~15.8%. The pH of wines ranged from 2.92 to 2.94 and the total acidity and soluble solid of wines ranged from 12.40~13.27. °Brix. The major organic acid in the wines was tartaric acid (4.49~5.11 mg/mL) and malic acid (7.00~7.97 mg/mL). It contains higher functional compounds in wine fermented with yeast (EJ18, EJ30, HK22, HK32) than wine fermented with fermivin. α-glucosidase and tyrosinase inhibitory activity had the highest values (78.87% and 62.25%) in wine fermented with HK22 and EJ18 yeast, respectively. 16 volatile flavor compounds (alcohols, esters, ketones, acids, and others) were detected in the Cheongsoo wines by freeze concentration. These results provide useful information that the quality characteristics of wine developed by the freeze-concentration method using grapes cultivated in Korea.

• Korean journal of food and cookery science
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• v.31 no.3
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• pp.296-303
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• 2015

We investigate black raspberry (Rubus occidentalis) wine made using traditional yeast (Saccharomyces cerevisiae A8, B6, GBY2, GBY3) and S. cerevisiae Fermivin (FM), which is widely used in wine manufacturing, and analyze the biogenic amine content and the volatile flavor compounds. Black raspberries were separately inoculated with yeast up to $1{\times}10^9CFU/kg$, followed by incubation at $25^{\circ}C$ for 7 days. FM produced the highest alcohol content, however the final fermentation characteristics of the wine made using four different yeasts were similar. S. cerevisiae A8 had a large biogenic amine (BA) content, specifically tryptamine, thus we excluded this yeast from fermentation. S. cerevisiae GBY3 was selected for black raspberry wine fermentation as a result of sensory evaluation. The volatile flavor compounds of two wines (S. cerevisiae GBY3 and FM) were analyzed by gas chromatography and mass spectrometry. 37 compounds in the samples were separated, and several ester compounds were identified in greater amounts in the wine made with S. cerevisiae GBY3 than in the wine made with FM. A greater amount of the major compound, ethyl benzoate, giving the sweet and fruity flavor, was identified in wine made with S. cerevisiae GBY3 than in the wine made with FM. In conclusion, S. cerevisiae GBY3 was confirmed to produce no major BAs and a better flavored wine. These results give new leads in the production of high quality wine.

• Journal of Microbiology and Biotechnology
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• v.30 no.12
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• pp.1876-1884
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• 2020

Ethanol often accumulates during the process of wine fermentation, and mitophagy has critical role in ethanol output. However, the relationship between mitophagy and ethanol stress is still unclear. In this study, the expression of ATG11 and ATG32 genes exposed to ethanol stress was accessed by real-time quantitative reverse transcription polymerase chain reaction (qRT-PCR). The result indicated that ethanol stress induced expression of the ATG11 and ATG32 genes. The colony sizes and the alcohol yield of atg11 and atg32 were also smaller and lower than those of wild type strain under ethanol whereas the mortality of mutants is higher. Furthermore, compared with wild type, the membrane integrity and the mitochondrial membrane potential of atg11 and atg32 exhibited greater damage following ethanol stress. In addition, a greater proportion of mutant cells were arrested at the G1/G0 cell cycle. There was more aggregation of peroxide hydrogen (H2O2) and superoxide anion (O2•-) in mutants. These changes in H2O2 and O2•- in yeasts were altered by reductants or inhibitors of scavenging enzyme by means of regulating the expression of ATG11 and ATG32 genes. Inhibitors of the mitochondrial electron transport chain (mtETC) also increased production of H2O2 and O2•- by enhancing expression of the ATG11 and ATG32 genes. Further results showed that activator or inhibitor of autophagy also activated or inhibited mitophagy by altering production of H2O2 and O2•. Therefore, ethanol stress induces mitophagy which improves yeast the tolerance to ethanol and the level of mitophagy during ethanol stress is regulated by ROS derived from mtETC.

• Korean Journal of Agricultural Science
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• v.12 no.2
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• pp.272-281
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• 1985

The ginseng extract was investigated for their effects on the fermentation of Kluyveromyces fragilis IFO 0288, and the addition of 0-5.0% of ginseng extract from skim milk media were compared to its effects during suspension culture at $30^{\circ}$ for 168 hours. The results are summarized as follows; 1. The addition of 1.0% and 5.0% ginseng extract were significantly increased pH and acidity compared to control. 2. $CO_2$ evolution was significantly in 1.0% but inhibited in 5.0% ginseng extract 3. Alcohol production was more producted and shortened of fermentation time in 1.0-5.0% than 0-0.5% added groups. 4. The number and growth rates of yeast was shortened inductive phase and lengthened extinctive phase in 1.0-5.0% added groups. 5. Free sugar contained in ginseng extract was not significantly affected by fermentation of yeasts.

• Korean Journal of Food Science and Technology
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• v.26 no.1
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• pp.6-11
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• 1994

A cyclodextrin glucanotransferase(CGTase)-producing Bacillus sp. I-5 was isolated from soil and the enzyme exhibited the maximum reaction rate at pH 8.0 and $50^{\circ}C$. It was found that CGTase of I-5 produced ${\beta}-$ and ${\gamma}-CD$ mainly but the production ratio of cyclodextrins (CDs) was influenced by the buffer solution. Sodium acetate significantly stimulated the formation of ${\gamma}-CD$, increasing the content by 35%. The production of CDs was influenced by DE value of starch. The results indicated that DE value in the range of $3.5{\sim}6.0$ were most effective for the CD formation. CGTase was immobilized on the reversibly soluble-insoluble carrier, hydroxypropyl mothylcellulose acetate succinate. The immobilized CGTase was soluble at pH 7.5, and precipitated easily at pH 6.0. Enzyme reactor was designed to produce CD continuously. It was composed of three major stages-CD produttion by immobilized CGTase, conversion of the residual dextrin to glucose by amylase and glucoamylase and alcohol fermentation by yeasts to remove the glucose into alcohol. The yield of total CDs was 3.65g from 10g soluble starch.

• The Journal of Industrial Distribution & Business
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• v.2 no.1
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• pp.23-28
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• 2011

In recent years Mag-Geol-Li is becoming popular again and the consumption layer of Mag-Geol-Li is definitely younger. Nowadays, Mag-Geol-Li is the main traditional alcohol and without consideration of ages and genders whoever can enjoy Mag-Geol-Li. Producers should ensure fair price of goods and improve production facilities to maximize products to meet the needs of consumers who will buy. In the studies I discuss about the ways to improve the distribution of Mag-Geol-Li, the theories about Mag-Geol-Li, Social backgrounds and effects of Mag-Geol-Li why it is becoming popular and improvement of the distribution structure of Mag-Geol-Li and impact of big Mag-Geol-Li company in Mag-Geol-Li industry. Lately, people can enjoy Mag-Geol-Li without burden because of low alcohol. It is gaining a good response by consumers because Mag-Geol-Li contains lactobacillus, yeasts and dietary fiber, also it is well balanced with nutritional aspects. There are not only huge factory to produce Mag-Geol-Li but also most are still cottage industry. Therefore, quality management does not work well because the majority of Mag-Geol-Li is small businesses. In spite of there are a lot of ways to improve the distribution structure and problems of Mag-Geol-Li, but none provide any improvement that make consumer awareness about the main cause of the problem is inaccurate. The ultimate goal of improving the distribution structure of Mag-Geol-Li is activating the market, the improvement of production facilities and safe for consumers with affordable price and good quality product. As mentioned above, to improve and change the logistics systems and hygiene, government support is required and Mag-Geol-Li companies should be recognized the distribution system as a major problem.