• Food Science and Biotechnology
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• v.18 no.6
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• pp.1358-1364
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• 2009

Electric polarity of working electrode and counter electrode was periodically switched at the intervals of 30 sec. Electric current generated by anodic and cathodic reaction of working electrode was reached to +30 and -12 mA in low intensity pulsed electric field (LIPEF). The yeast growth, ethanol production, and malate consumption in the initial cultivation time were more activated in the LIPEF than the conventional condition (CC). Polyphenol, total phenolic contents (TPC), and total flavonols (TF) were gradually decreased in all cultivation conditions during incubation for 2 weeks but antioxidation activity was not. TF was significantly lower in 3 and 4 V of LIPEF than CC and 2 V of LIPEF; however, the polyphenol, TPC, and antioxidation activity were a little influenced by the LIPEF. After ripening of the winemaking culture for 15 days, polyphenol, TPC, and TF were a little increased but the antioxidation activity was not.

• Journal of Microbiology and Biotechnology
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• v.21 no.12
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• pp.1243-1249
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• 2011

This study was performed to examine the use of NaOCl as an alternative antimicrobial compound in winemaking because of the potential health problems that may arise as a result of the use of $SO_2$. For this, the blank (non-treated), control ($SO_2$-added), and sample (NaOCl-treated) wines were made, and microbial and chemical changes including sensory characteristics were analyzed during the fermentation periods. Treatment of grapes with NaOCl decreased the initial contaminating microbial population in grape must, resulting in higher growth of yeast and lactic acid bacteria. After 200 days of fermentation, the chemical analysis of sample wine revealed that it had higher ethanol content, redness ($a^*$), and concentrations of fruity ester compounds and lower total acidity than the control. In the sensory analyses, the sample wine obtained a higher overall acceptability score (5.70) than the control (4.26). This result reveals that NaOCl can be used as an alternative to $SO_2$ in winemaking for inhibiting the growth of contaminating microorganisms.

• Iberoamérica
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• v.23 no.2
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• pp.209-241
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• 2021

Over the last few years, rural areas in northeastern Mexico have present significant changes in social, economic, and territorial aspects linked to the New Rurality. In this context, winemaking has become one of the most dynamic and growing activities in the regional economy. This emerging development has prompted different forms of appropriation and use of this space, but it also highlights the lack of access to knowledge for wine production due to the lack of formal educational centers. As a result, learning communities enable the development of skills and competencies through non-formal educational practices. The objective of this paper is to analyze the role of learning communities in non-formal educational environments, taking as a case study: a collective of small-scale wine producers in Parras de la Fuente, Coahuila. This research focuses on two perspectives of learning: appropriation and technology transfer, and promotion of Mexican wine culture. The main finding was to demonstrate the importance of including educational processes that respond to the context and needs of the community.

• The Korean Journal of Food And Nutrition
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• v.10 no.2
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• pp.254-262
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• 1997

new wild grape(NWG) cultivated in north Kyungki province in Korea, was tested by analyzing the proximate and physicochemical components of fresh fruit, the chemical components and sensory evaluation of wines made from the grape. NWG contained about 10% seed, and about 70% of juice. Total sugar content, total acidity and pH of the fruit juice were 17.50, 1.14 and 3.48%, respectively. Tartaric acid and malic acid contents of the NWG juice were 0.396 and 0.509%, respectively. Ethanol fermentation of the NWG by Saccharomyces cerevisiae Montrachet was rapid. The ethanol content, total acidity and pH of pink wine made from the NWG juice showed 11.88, 0.85 and 3.55%, respectively. Tartaric acid and malic acid contents of pink wine were 0.208 and 0.421%, respectively. Total anthocyanin content(A520) and color intensity(A520+A420) of pink wine were 5.46 and 9.39, showing greatly higher total anthocyanin content and color intensity than those of European red wines. Total phenol contents of NWG wine were 2, 300~3, 800mg/$\ell$. The pink wine made from the fruit juice was better than the red wine in their quality parameters and sensory scores.

• The Korean Journal of Food And Nutrition
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• v.9 no.3
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• pp.265-270
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• 1996

When new told grape with high acidity Is used wine, their sensory scores are decreased. Using three available methods reducing excess acidify In winemaking, they were malo-lactic fermentation, addition of apple pomace and malo-alcohol fermentation. The chemical monponents and sensory evaluation of wine were determined. They were found in pink wine added apple pomace that tatal acidity and malic acid content were 0.76 and 0.484%. Color Intensity (A520+A420) in pink wanes, their valuse were in the range 8.21~9.42, while the value of red wine was 20.92. Browning index and total phenol contents in pink wine, their values were In the range of 1.36∼1.42 and 3,300∼3,800mg 11. The sensory evaluation showed that the pink wine added apple pomace(10%) was highest in taste and total scores (P<0.05), and the taste of wine has improved.

• 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 Microbiology and Biotechnology
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• v.29 no.9
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• pp.1341-1348
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• 2019

Acetic acid is indirectly involved in cell center metabolism, and acetic acid metabolism is the core of central metabolism, affecting and regulating the production of bacteriocin. Bacteriocin is a natural food preservative that has been used in the meat and dairy industries and winemaking. In this paper, the effects of acetic acid on bacteriocin produced by Gram-positive bacteria were reviewed. It was found that acetic acid in the undissociated state can diffuse freely through the hydrophobic layer of the membrane and dissociate, affecting the production, yield, and activity of bacteriocin. In particular, the effect of acetic acid on cell membranes is summarized. The link between acetic acid metabolism, quorum sensing, and bacteriocin production mechanisms is also highlighted.

• Food Science and Preservation
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• v.22 no.1
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• pp.91-99
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• 2015

This study investigated the phenolic compounds of must and wine supplemented with different concentrations (0% (no added stems), 1%, 2%, 3%, and 5%) of fruit stems during winemaking using Muscat Bailey A (MBA) grapes. The red color, and total anthocyanin, total polyphenol, and tannin contents of the must and wine significantly (p<0.05) increased with increasing added amounts of grape fruit stems, while the volatile acid content decreased with increasing added amounts of grape fruit stems. Catechin (8.16~23.08 mg/L), gallic acid (2.32~3.28 mg/L), trans-resveratrol (1.38~3.27 mg/L), and ferulic acid (1.51~1.59 mg/L) were detected in the must and wine via HPLC. The bioactive substance contents increased with increasing added amounts of grape fruit stems, except for ferulic acid. The DPPH $IC_{50}$ activity was higher in the wine (12 mg/L) with 5% grape fruit stems than in ascorbic acid (67 mg/L). These results suggest that the fruit stems of MBA grapes can be used as functional materials for winemaking.

• Journal of Microbiology and Biotechnology
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• v.19 no.9
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• pp.1005-1012
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• 2009

Lysozyme and the reduction of metabisulfite addition to red wine were evaluated during a winemaking process and after malolactic fermentation (MLF). Treatment, with lysozyme, of the must from Tempranillo grapes and at the end of alcoholic fermentation (AF) caused the 100% implantation of the inoculated bacterial strain and shortened the duration of MLF by 7 days. At the end of the MLF, wines treated with lysozyme showed lower volatile acidity, color intensity, and biogenic amine content. The differences in color intensity disappeared during wine stabilization. The lysozyme addition after MLF led to lower histamine concentrations in wines. These phenomena occurred irrespective of the lactic acid bacteria (LAB) proliferation control and of the Oenococcus oeni dominant strain identified at this period. The results of this study show the significance of preventive use of lysozyme in vinification of red wine to maintain low histamine levels and ensure a successful implantation of inoculated O. oeni starters.

• Journal of Microbiology and Biotechnology
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• v.20 no.7
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• pp.1121-1127
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• 2010

This study was performed to investigate the effects of adding a dual starter on the chemical and sensory characteristics of red wine made of Campbell Early grape. The yeast starter, Saccharomyces cerevisiae, and lactic acid bacteria (LAB) starter, Oenococcus oeni, were used for inoculation in the winemaking process for alcoholic fermentation and malolactic fermentation (MLF), respectively. After 200 days of incubation, the chemical compositions of yeast/LAB-added wine (YL-wine) were compared with those of no-starter-added wine (control) and yeast-added wine (Y-wine). The results show that no significant differences were observed in pH, total sugar, and alcohol content among the wine samples, but the malic acid content in YL-wine was significantly reduced, and various esters and higher alcohols were synthesized. The sensory test revealed that the addition of dual starters resulted in improved overall acceptability in wine. This study emphasizes the importance of O. oeni in addition to yeast in making Campbell Early wine.