• Journal of the East Asian Society of Dietary Life
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• v.18 no.4
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• pp.547-553
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• 2008

The principal objective of this study was to prepare watermelon wine with watermelon juice. For the manufacture of watermelon wine, we determined the contents of starting sugar content ($20^{\circ}Brix$, $25^{\circ}Brix$, $30^{\circ}Brix$, $35^{\circ}Brix$) and three different kinds of yeasts (EC-1118, K1-V1116, D-47). The main additives of the watermelon wine included $K_2S_2O_5$, $NH_4H_2PO_4$, bentonite, yeasts, sugar, mixed acid, and $C_6H_8O_2$. The watermelon wine was fermented at $15^{\circ}C$ until the remaining alcohol content was 5%. We assessed customers' preference regarding the manufactured watermelon wine via sensory evaluation. Three yeasts were shown to result in significantly different alcohol fermentation, among which K2-V1116 was selected for the preparation of the watermelon wine. In our sensory evaluation, the preference of the starting sugar contents was highest in the watermelon wine with $25^{\circ}Brix$ of sugar content. The preference of alcohol content was found to be higher in the watermelon wines prepared with sugar contents of 5% and 7%. The preference test between watermelon wines and purchased white wines demonstrated that the watermelon wine with an alcohol content of 5% was the most preferred wine, and the Chilean Late Harvest wine was the second most preferred.

• Microbiology and Biotechnology Letters
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• v.18 no.1
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• pp.1-5
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• 1990

This study was performed to isolated woild killer yeasts which might suppress the growth of contaminant yeasts during wine making. Seventeen strains of killer yeasts which were isolated from grapes in Korea showed different killing activity; higher with K109 and K112. and lower with K117 strain. There was no inhibition among the isolates by cross-reaction. Through the physiological, morphological and cultural test, the isolates were identified as a new killer yeast, Cadida dattila, and then named Candida dattila K101-K117.

• Journal of the East Asian Society of Dietary Life
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• v.26 no.6
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• pp.543-549
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• 2016

The objective of this study was to investigate quality properties of 'Cheonghyang' wine using different commercial yeast strains. Soluble solid content, pH level and total acidity of 'Cheonghyang' grape were $20^{\circ}Bx$, pH 3.5 and 0.66%, respectively. Total acidity ranged from 0.91~1.06% in the middle stage of fermentation and decreased to 0.77~0.82% when alcoholic fermentation finished. Alcohol content in wines ranged from 12.5% to 12.9% showing no significant difference in yeast strains. Wine fermented with Red Fruit had high volatile acid content (189.0 mg/L) whereas wine fermented with Fermivin indicated low volatile acid content (77.7 mg/L). Wines made with Montrachet, Fermivin and Aroma White had low brightness (L-value) compared to others. Results from sensory evaluation demonstrated that commercial wine yeasts, Montrachet and Fermivin, can be applied to improve sensory properties of 'Cheonghyang' wine such as aroma, acidity and transperency. On the other hand, preferences of wine fermented with EC-1118 strain containing lots of tannins and total polyphenols were significantly reduced.

• Mycobiology
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• v.39 no.1
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• pp.33-39
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• 2011

Wild yeasts on the surface of various fruits including grapes were surveyed to obtain yeast strains suitable for fermenting a novel wine with higher alcohol content and supplemented with rice starch. We considered selected characteristics, such as tolerance to alcohol and osmotic pressure, capability of utilizing maltose, and starch hydrolysis. Among 637 putative yeast isolates, 115 strains exhibiting better growth in yeast-peptone-dextrose broth containing 30% dextrose, 7% alcohol, or 2% maltose were selected, as well as five ${\alpha}$-amylase producers. Nucleotide sequence analysis of the 26S rDNA gene classified the strains into 13 species belonging to five genera; Pichia anomala was the most prevalent (41.7%), followed by Wickerhamomyces anomalus (19.2%), P. guilliermondii (15%), Candida spp. (5.8%), Kodamaea ohmeri (2.5%), and Metschnikowia spp. (2.5%). All of the ${\alpha}$-amylase producers were Aureobasidium pullulans. Only one isolate (NK28) was identified as Saccharomyces cerevisiae. NK28 had all of the desired properties for the purpose of this study, except ${\alpha}$-amylase production, and fermented alcohol better than commercial wine yeasts.

• The Korean Journal of Food And Nutrition
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• v.16 no.3
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• pp.203-208
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• 2003

In wine making, to perform yeast culture effectively that is the most important factor, 5 (Montrachet, Pasteur Champagne, Epernay II, prise de Mousse, Lalvin W15) representative active dry yeasts were selected. These are results about physicochemical properties. As a consequence of examining the survival rate in both 17% ethanol solution and 200ppm sulfite solution after 72 hours, Lalvin W15 strain was the highest among the 5 representative active dry yeasts. Moreover, in 1% citric acid solution, the survival rate of Pasteur Champagne after 72 hours was the highest one. As a result of experiment of red wine that is fermented by 5 different active dry yeasts, the highest one of total acidity was must of Lalvin W15. And then, the must of the Epernay II contains the highest ethanol content. Regarding of the content of organic acid, the wine that is fermented by Prise de mousse was the highest one and the order could be explained by Tartaric > Malic > Citric.

• Korean Journal of Agricultural Science
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• v.2 no.2
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• pp.445-450
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• 1975

These experiments were carried out to obtain useful yeast for Korean grape wine brewing. The 213 strains of yeasts were isolated from grapes sampled in Daejeon city and suburbs and then 3 strains among the isolated yeasts were selected as useful strains and identified. The results obtained as follows; 1. The 3 strains of W-49, W-50 and W-127 selected as useful yeasts were clarified to grape wine mash rapidly. 2. In the mashes clarified after storage of 45 days, the value of optical density of the case of W-50 strain was highest and the color was very thick, compared with the case of another strains. 3. In the pannel test of the grape wines, the case of W-49 and W-50 strains were best, the case of the W-127 strain and control yeast, Hb were similar each other as next order. 4. Among 3 strains selected as useful yeasts it were identified that the strains of W-49, W-50 selected as useful strains were Saccharomyces cerevisiae and the strain of W-127 was Saccharinyces pretoriencis by the Ladder manual. 5. All of these useful yeasts were appeared red color on TT C stain.

• Korean Journal of Food Science and Technology
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• v.14 no.3
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• pp.236-243
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• 1982

In order to remove the high content of malic acid (0.48%) in freshly fermented apple wine by applying malo-alcoholic fermentation(MAF) using malate-decomposing yeasts, Schizosaccharomyces japonicus var. japonicus or Schizosaccharomyces pombe, some factors which influenced malic acid decomposition in apple wine by malate-decomposing yeasts were investigated. By incubating the apple wine with these yeasts, 80% of initial malic acid was decomposed in 13 days at $20^{\circ}C$, whereas only 32% reduction in malic acid was observed in 40 days when MAF was not induced. For malic acid decomposition, Schizosaccharomyces pombe was superior to Schizosaccharomyces japonicus var. japonicus in natural medium such as apple wine, whereas Schizosaccharomyces japonicus var. japonicus was superior to Schizosaccharomyces pombe in synthetic medium. The optimum temperature for the MAF using these yeasts was between $20\;to\;30^{\circ}C$ and no adverse effect was detected by the addition of $SO_2$ up to 200ppm. Additions of $Mg^{2+}$ or certain amino acids such as alanine, aspartic acid to the wine could enhance the composition of malic acid.

• Food Science and Biotechnology
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• v.14 no.6
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• pp.722-726
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• 2005

The use of isolated wine yeasts in winemaking processes is preferable to spontaneous fermentation. Selection criteria of wine yeast strains depend also on capacity and rate of fermentation and on alcohologenic capabilities. Our studies have described the dynamics of fermentation of wine musts by some isolated wine yeast strains of Saccharomyces genus: strains 6 and 8 of S. cerevisiae var. ellipsoideus (S. ellipsoideus) and strains 5 and 7 of S. bayanus var. oviformis (S. oviformis). All have high technological properties and all are adapted for the specific pedoclimatic conditions of some areas of Sibiu viticultural region. The selected strains were used as inocula to ferment Sauvignon, Muscat Ottonel, Rose Traminer, and Pino Gris musts in controlled laboratory conditions. It was found that higher initial oxygen concentration in must is necessary to accelerate the fermentation of all the wine yeast strains studied. In order to obtain quality wines, strains with considerable fermentative capacity, high alcohologenic capabilities, and a good conversion efficiency are recommended.

• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.12
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• pp.1860-1866
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• 2010

The purpose of this research was to characterize physicochemical properties and sensory evaluation of schizandra wines fermented by the yeasts, Sacchromyces cerevisiae SH8094 (S. cerevisiae SH8094) and Sacchromyces cerevisiae SH2855 (S. cerevisiae SH2855) isolated from schizandra fruits and stems and compare these results with the results from commercial activated yeast (Lalvin 1118) and a commercial schizandra wine. Three different schizandra wines fermented by S. cerevisiae SH8094, S. cerevisiae SH2855, and Lalvin 1118 showed similar results in pH and titratable acidity. On the other hand, the schizandra wines fermented by S. cerevisiae SH8094 and S. cerevisiae SH2855 showed high brix ($14^{\circ}$brix), low alcohol content (9%), and low yeasts count (4.1 log CFU/mL), compared with the schizandra wine fermented by Lalvin 1118. Both schizandra wines made with S. cerevisiae SH8094 and S. cerevisiae SH2855 showed higher scores in swallowing and overall acceptability than the schizandra wine made with Lalvin 1118. When compared with a commercial schizandra wine, the schizandra wine fermented with S. cerevisiae SH8094 showed better qualities in aroma ($6.65{\pm}1.47$), color ($7.53{\pm}1.14$), and overall acceptability ($6.76{\pm}1.03$). In conclusion, S. cerevisiae SH8094 which was isolated from schizandra fruits and stems has a high potential in schizandra wine fermentation.

• Microbiology and Biotechnology Letters
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• v.43 no.3
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• pp.227-235
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• 2015

The objective of this study was to improve the quality of Korean rice wine with wild type yeast strains isolated from various traditional Korean fermented foods. Herein the fermentation and sensory characterization of wild yeast, for the purposes of brewing Korean rice wine, was investigated. 12 yeast strains were examined for their ethanol and glucose tolerance. In addition, the pH, soluble solids, acidity, amino acidity, ethanol content, organic acids, and volatile compounds were also studied for the alcoholic beverages made with the wild yeasts. Almost all Saccharomyces genera yeasts were showed to have a tolerance at 10% ethanol, but non-Saccharomyces genera yeasts displayed a low tolerance. The alcoholic beverages fermented by non-Saccharomyces yeasts demonstrated higher levels of soluble solids, titratable acidity, amino acids, and lower ethanol content, when compared with the alcoholic beverages fermented by Saccharomyces genera yeasts. The organic acid content, such as malic acid, acetic acid, and succinic acid, was seen to also be higher. The electronic nose was analyzed, and discriminant function analysis (DFA) was used for discriminating wild yeast strains. The DFA plots indicated a significant separation of Saccharomyces genera and non-Saccharomyces yeast strains. For volatile compounds, ethyl acetate from non-Saccharomyces yeasts, and ethanol from Saccharomyces genera yeast, a high area ratio was observed.