• Food Science and Preservation
• /
• v.15 no.1
• /
• pp.150-154
• /
• 2008

This study investigated 1he fermentation characteristics and sensory properties of white wine made from the Chilean grape varieties Thomson Seedless (T), Red Globe (R), and a mixture thereof (M). The pH fell during fermentation and final pH values of 3.63-3.68 were slightly higher than is usual in white wine. The total acidity increased during the alcoholic fermentation and leveled at 0.56-0.71% Ater 15d, the sugar contents and specific gravities attained final values. The L value of wine made from R grapes increased from 65.05 to 96.77, of wine made from T grapes from 77.41 to 99.6, and of wine made from M grapes from 71.73 to 98.41. The a value of all wines decreased quickly during the first 4 d of fermentation and the b values of T and M wines (not R wine) also fell rapidly during this time. The final alcohol concentrations of the wines were 14 -14.9% (v/v). The white wines made from T, R, and M grapes received similar scores in a directional difference sensory test. The color and flavor of white wine made from T grapes scored highest (5.6 and 5.35 respectively; p<0.05 for both values), but overall acceptabilities of all three wines were similar (4.30-4.85, p<0.05).

• Food Science and Preservation
• /
• v.16 no.6
• /
• pp.977-984
• /
• 2009

Campbell Early grapes, the major grape variety in Korea, contain 13 - 15% (w/v) sugar, which is lower than that appropriate for fermentation of red wine. Therefore, chaptalization with sucrose is usually used to increase the sugar level to an extent adequate to produce a wine containing about 12% (v/v) alcohol. In the present study, fermentation of freeze-concentrated Campbell Early grape juice at $25^{\circ}Brix$ was investigated using several industrial wine yeasts including Saccharomyces cerevisiae OC2, S. cerevisiae Fermivin, and S. cerevisiae W-3. During fermentation, changes in the levels of soluble solids, alcohol, total acid, and yeast viable counts were investigated. Alcohol content reached maximal levels after 9 days of fermentation, and was 12.6% (v/v) when the Fermivin strain was used and 13% (v/v) when each of the OC2 and W-3 strains was used. No significant between-strain difference was found, except for slightly slower alcohol production and sugar consumption, and a higher total acid content when strain OC2 was used. Changes in the yeast viable counts were similar during fermentation. The physicochemical characteristics of Campbell Early wine prepared using freeze-concentrated juice were investigated by measuring the levels of total phenolic compounds, organic acids, acetaldehyde, and minor alcohols and assessment of color values. Similar levels of soluble solids and total phenolic contents were observed in wines fermented by the three different strains, but a higher level of total acid was noted in OC2-fermented wine and a lower level of alcohol in Fermivin-fermented wine. The highest level of malic acid and the lowest level of lactic acid were detected in Fermivin-fermented wine. Although the wines showed variable levels of acetaldehyde and minor alcohols, the concentrations of these materials were much lower than those mandated by legal regulations promulgated by the Korean National Tax Service. Red and violet colors in OC2-fermented wine were darker than those of W-3-fermented wine. In sensory evaluation, W-3-fermented wine obtained the highest scores for color and flavor. However, the best taste score was reported for the OC2-fermented wine, whereas Fermivin-fermented wine was awarded the highest score in overall acceptance.

• Korean Journal of Food Science and Technology
• /
• v.35 no.3
• /
• pp.386-392
• /
• 2003

Physicochemical and microbiological changes of grape wine fermented and aged at 25 and $15^{\circ}C$ for 2 and 14 weeks, respectively, were investigated. Viable bacterial cell number, $3.3{\times}10^2\;CFU/mL$ at the beginning of fermentation, increased to $2.3{\times}10^6\;CFU/mL$ after 2 weeks, then decreased to $1.9{\times}10^3\;CFU/mL$ after 14 weeks. Viable yeast cell number increased from $2.8{\times}10^2\;to\;2.2{\times}10^7\;CFU/mL$ during fermentation, then decreased to $1.6{\times}10^4\;CFU/mL$ after aging. Turbidity, pH, total sugar content, reducing sugar content, and solid content of grape wine decreased during fermentation, whereas acidity and alcohol content increased to 0.64 and 8.4%, respectively. Most physicochemical properties did not change significantly during aging. When grape wine was filtered through $0.45-{\mu}m$ nitrocellulose membrane, followed by various ultrafiltration membranes with different molecular weight cut-off values, Biomax 100K membrane with $100\;L/m^2/hr$ (LMH) of initial flux was chosen for ultrafiltration process. These membrane filtration treatments resulted in complete removal of microorganisms and decreases in turbidity, reducing sugar, and solid content. Physicochemical properties of wine did not change, and no microorganisms were found during storage at $30^{\circ}C$ for 12 weeks.

• Food Science and Preservation
• /
• v.15 no.2
• /
• pp.306-310
• /
• 2008

This study investigated the effects of 3 different strains of my yeast (Saccharomyces cerevisiae Montrachet (UCD #522), S. bayanus Pasteur Champagne (UCD #595), and S. cerevisiae Epernay (CEG) and two grape varieties (Tamnara and M.B.A) on the quality of red wines. During fermentation, sugar content decreased and alcohol content increased Addition of my yeast increased fermentation speed for both grape varieties. Sensory quality tests and tests with an electronic tongue showed that red wine made from M.B.A grapes was superior to that made from Tamnara grapes and that red wine made without the addition of my yeast was better than that made by using dry yeast.

• Proceedings of the Plant Resources Society of Korea Conference
• /
• 2012.05a
• /
• pp.4-4
• /
• 2012

• Korean Journal of Food Science and Technology
• /
• v.52 no.3
• /
• pp.284-289
• /
• 2020

The cultivars of wine grapes 'Doonuri', 'Narsha', 'Cabernet Sauvignon', and 'Merlot' were cultivated in Modified-T (MT), Modified-T Cane pruning (MTC), and Geneva Double Curtain (GDC) trellises, and the changes in vine growth, fruit and wine characteristics were compared for two years (2018 and 2019). With respect to the vine growth characteristics, the wine grape cultivars cultivated in the GDC trellis were significantly inferior to those cultivated in the MT or MTC trellises. The grape yields of the cultivars cultivated in GDC trellise increased by 1.5 to 2 times cultivated in the GDC trellises compared to those cultivated in the other trellis, however, the fruit characteristics (total soluble solids, titratable acidity, and berry weight) did not differ among the differently cultivated groups. Moreover, the anthocyanin content and red color of the wine were significantly enriched in all red wine grape cultivars cultivated in the GDC trellises.

• Journal of the East Asian Society of Dietary Life
• /
• v.24 no.4
• /
• pp.457-464
• /
• 2014

This study investigated the effects and interrelationship on sensual behavior and wine information sources in selection attributes of wine. Selection attributes of wine were categorized into four variables: sensual behavior, recommend information, label information, and wine information. The study showed that for sensual behavior variable, "taste" was the most influential item as compared to "food harmony", "mood harmony" and "partner's choice". For recommendation information, label information and wine information, "specialist", "grape varieties" and "brand" had the most significant effects. The study performed factor analysis on sensual behavior and wine information sources. The cumulative variance was 74.197%, implying that all four variables incorporated appropriate items. In the reliability analysis, all four variables showed Cronbach's ${\alpha}$ values above 0.6. In the analysis of the causal relations using a structural model, the effects of customers' sensual behavior on wine information sources was further investigated. The model verified that taste, food harmony, mood harmony and partner's choice, which are items of sensual behavior, had significant impacts when choosing wine. Sensual behavior influenced all wine information sources, which customers utilize in decision-making. Among these sources, sensual behavior had the biggest effects on recommendation information, followed by wine information and label information.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.46 no.5
• /
• pp.622-629
• /
• 2017

This study was carried out to investigate the effects of cold maceration and heat treatment prior to alcohol fermentation on the quality characteristics of wine made from Okrang grape cultivar. The results of this study show that alcohol contents of wines increased as fermentation period increased, whereas $^{\circ}Brix$ values decreased. The pH levels of wines ranged from 3.17 to 3.42 while the total acidities of wines ranged from 0.49~0.99%. The free sugar contents of wines tended to decrease as fermentation period increased. In particular, free sugar content of wine pre-treated at low temperature prior to alcohol fermentation slowly. Total polyphenol content of wine heat-treated prior to alcohol fermentation was higher than those of other wines and reached a maximum value after fermentation for 2 days. Campbell Early wine showed the strongest antioxidant effect, measured based on DPPH free radical scavenging activity, followed by Okrang wine pressing after fermentation. These results indicate that pre-treatment before wine fermentation greatly affects wine quality and biofunctional activities.

• Nutrition Research and Practice
• /
• v.6 no.4
• /
• pp.286-293
• /
• 2012

Resveratrol (3,4,5-trihydroxy-trans-stilbene), a phytoalexin found in grape skin, grape products, and peanuts as well as red wine, has been reported to have various biological and pharmacological properties. The purpose of this study was to investigate the anti-obesity effect of resveratrol-amplified grape skin extracts on adipocytes. The anti-obesity effects of grape skin extracts were investigated by measuring proliferation and differentiation in 3T3-L1 cells. The effect of grape skin ethanol extracts on cell proliferation was detected by the MTS assay. The morphological changes and degree of adipogenesis of preadipocyte 3T3-L1 cells were measured by Oil Red-O staining assay. Treatment with extracts of resveratrol-amplified grape skin decreased lipid accumulation and glycerol-3-phosphate dehydrogenase activity without affecting 3T3-L1 cell viability. Grape skin extract treatment resulted in significantly attenuated expression of key adipogenic transcription factors, including peroxisome proliferator-activated receptor, CCAAT/enhancer-binding proteins, and their target genes (FAS, aP2, SCD-1, and LPL). These results indicate that resveratrol-amplified grape skin extracts may be useful for preventing obesity by regulating lipid metabolism.

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