• Proceedings of the Korean Society of Near Infrared Spectroscopy Conference
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• 2001.06a
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• pp.1253-1253
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• 2001

The ability to accurately assess wine quality is important during the wine making process, particularly when allocating batches of wines to styles determined by consumer requirements. Grape payments are often determined by the quality category of the wine that is produced from them. Wine quality, in terms of sensory characteristics, is normally a subjective measure, performed by experienced winemakers, wine competition judges or winetasting panellists. By nature, such assessments can be biased by individual preferences and may be subject to day-to-day variation. Taste and aroma compounds are often present in concentrations below the detection limit of near infrared (NIR) spectroscopy but the more abundant organic compounds offer potential for objective quality grading by this technique. Samples were drawn from one of Australia's major wine shows and from BRL Hardy's post-vintage wine quality allocation tastings. The samples were scanned in transmission mode with a FOSS NIR Systems 6500, over the wavelength range 400-2500 ㎚. Data analysis was performed with the Vision chemometrics package. With samples from the allocation tastings, the best correlations between NIR spectra and tasting data were obtained with dry red wines. These calibrations used loadings in the wavelengths related to anthocyanins, ethanol and possibly tannins. Anthocyanins are a group of compounds responsible for colour in red wines - restricting the wavelengths to those relating to anthocyanins produced calibrations of similar accuracy to those using the full wavelength range. This was particularly marked with Merlot, a variety that tends to have relatively lower anthocyanin levels than Cabernet Sauvignon and Shiraz. For dry white wines, calibrations appeared to be more dependent on ethanol characteristics of the spectrum, implying that quality correlated with fruit maturity. The correlations between NIR spectra and sensory data obtained using the wine show samples were less significant in general. This may be related to the fact that within most classes in the show, the samples may span vintages, glowing areas and winemaking styles, even though they may be made from only one grape variety. For dry red wines, the best calibrations were obtained with a class of Pinot Noir - a variety that tends to be produced in limited areas in Australia and would represent the least matrix variation. Good correlations were obtained with a tawny port class - these wines are sweet, fortified wines, that are aged for long periods in wooden barrels. During the ageing process Maillard browning compounds are formed and the water is lost through the barrels in preference to ethanol, producing “concentrated” darkly coloured wines with high alcohol content. These calibrations indicated heaviest loadings in the water regions of the spectrum, suggesting that “concentration” of the wines was important, whilst the visible and alcohol regions of the spectrum also featured as important factors. NIR calibrations based on sensory scores will always be difficult to obtain due to variation between individual winetasters. Nevertheless, these results warrant further investigation and may provide valuable Insight into the main parameters affecting wine quality.

• Culinary science and hospitality research
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• v.10 no.1
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• pp.64-81
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• 2004

Recently, the demand for utensils related to wine business has been growing from the wine consumers in Korea in order to enjoy flavor of wine more profoundly. This study propose a theory about the five senses that had been issued frequently in wine world attracting an attention of ever-changing food culture. In addition, it is to help sommeliers and devotes to learn the knowledge about the wine. To fully appreciate the different grape varieties and the subtle characteristics of wines, it is essential to have a glass with shape if fine-tuned for the purpose. The shape is responsible for the quality and intensity of the bouquet and the flow of the wine. This study has been performed with Riedel glass that has been appreciated as one of the finest wineglass in the world to investigate the effect of glass to the wine tasting. This study should be followed by further study with other tasting glass such as INAO and Le Taster glass to be generalized. The study is also needed about not only wineglass but wine accessories such as cork-screw, decanting and wine cooler.

• Journal of the East Asian Society of Dietary Life
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• v.22 no.2
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• pp.264-270
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• 2012

The effect of pectinase on wine production and quality during wine fermentation was investigated in an experiment a laboratory scale (2 kg grape/5 L tank). Experimental results show that the enzyme-treated sample displayed a 13% higher rate of grape juice production compared to control (enzyme-untreated). In the case of color analysis, the addition of pectinase improved the color quality of wine in terms of both color intensity and hue values. The results show that pectinase enhanced both dark-red color and clarity of wine during the fermentation period. Further, the methanol concentration of the wine sample treated with pectinase reached 225.32 mg/L (control: 100.72 mg/L) due to hydrolysis of pectin. Sensory analysis after fermentation showed that pectinase significantly increased the color, smell, taste, and touch intensity scores of wines compared to control.

• Journal of Microbiology and Biotechnology
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• v.32 no.6
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• pp.761-767
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• 2022

EHT1 and EEB1 are the key Saccharomyces cerevisiae genes involved in the synthesis of ethyl esters during wine fermentation. We constructed single (Δeht1, Δeeb1) and double (Δeht1Δeeb1) heterogenous mutant strains of the industrial diploid wine yeast EC1118 by disrupting one allele of EHT1 and/or EEB1. In addition, the aromatic profile of wine produced during fermentation of simulated grape juice by these mutant strains was also analyzed. The expression levels of EHT1 and/or EEB1 in the relevant mutants were less than 50% of the wild-type strain when grown in YPD medium and simulated grape juice medium. Compared to the wild-type strain, all mutants produced lower amounts of ethyl esters in the fermented grape juice and also resulted in distinct ethyl ester profiles. ATF2, a gene involved in acetate ester synthesis, was expressed at higher levels in the EEB1 downregulation mutants compared to the wild-type and Δeht1 strains during fermentation, which was consistent with the content of acetate esters. In addition, the production of higher alcohols was also markedly affected by the decrease in EEB1 levels. Compared to EHT1, EEB1 downregulation had a greater impact on the production of acetate esters and higher alcohols, suggesting that controlling EEB1 expression could be an effective means to regulate the content of these aromatic metabolites in wine. Taken together, the synthesis of ethyl esters can be decreased by deleting one allele of EHT1 and EEB1 in the diploid EC1118 strain, which may modify the ester profile of wine more subtly compared to the complete deletion of target genes.

• 한국생물공학회:학술대회논문집
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• 2003.10a
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• pp.527-531
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• 2003

The interest of oligomeric proanthocyanidins(OPCs) as therapeutic agents against diseases involving radical damage is growing. Proanthocyanidins are a class of polyphenolic compounds in several plant species and are oligomers of flavan-3-ol monomer units. Polyphenols in green and black tea, grape seeds, grapes and wine have raised much attention but mountain grape seed has not been investigated intensively up to now This study investigated the total OPCs contents and the total antioxidant activity of mountain grape seeds. Total antioxidant activity using DPPH method was employed and OPCs contents were determined by means of the UV-VIS spectrophotometer. The total OPCs yield of mountain grape seeds was about 1.45 % and total antioxidant activity was 15.8 ${\mu}g/m{\ell}$.

• Journal of Environmental Health Sciences
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• v.12 no.1
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• pp.63-67
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• 1986

The contents of amino acid in alcoholic beverage-Cheongju, Beer, Makguli, grapewine were analyzed. Cheongju and Makguli were filtered with membrane filter paper. Beer and grapewine were also filtered after treatment with 5-Sulfosalicylic acid. Sample were analyzed by Amino Acid Analyzer (Hitach KLA-5). The results were as follow: 1. The kinds of Amino Acid in Cheongju were 18, those of Beer were 17, Makguli 15, and grape wine 10. 2. The total amino acid in Cheongju was 54.0295 mg, Beer was 16.7172mg, Makguli was 12.3833 mg and grape wine was 4.1480 mg in 100 ml volume.

• Korean Journal of Food Science and Technology
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• v.20 no.6
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• pp.787-793
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• 1988

Juices of Golden Queen, Neo-Muscat and Seibell-9110 were prepared with the addition of $SO_2(100ppm)$ in must and juice, of $SO_2(100ppm)$ and pectinase (40mg/l) in must, respectively and then 300mg/1 of Polyclar AT were added on different white wines from grape juices. Phenolics content in grape juices and white wines were determined. and also changes of browning capacity of white wines during the storage periods at $45^{\circ}C$ were investigated by accelerated method. Extraction of total phenol into grape juices was increased significantly in $SO_2-pectinase$ addition lot and content of total phenol of Seibell-9110 juice was two or three times higher than the others. Yield of grape juices was highest in $SO_2-pectinase$ addition lot. Ethanol content of white wines were 11.4-12.0 v/v% , and total acid, fusel oil and methanol content of Neo-Muscat white wine was lower than that of the other white wines. Total phenol content of white wines was 25-50% lower than that of grape juices and 50-80% lower in colour. Browning capacity of white wines was decreased by 25-40% for 18 days at $45^{\circ}C$ with addition of Polyclar AT, but Seibell-9110 white wine prepared from $SO_2-pectinase$ addition lot was not available commercially because of severe browning.

• The Korean Journal of Food And Nutrition
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• v.34 no.6
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• pp.621-630
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• 2021

In this study, we attempted to compare the maceration processes in the white wine made of Muscat of Alexandria grape having different the fermentation· maceration periods. These wine were sampled and analyzed by fermentation periods. The pH of wines ranged from 3.25 to 3.27 and the total acidity of wines ranged from 0.85~0.91% (w/v) on the 12th day of fermentation period. The ethanol concentration in these wines increased during the alcoholic fermentation period, on the other hand, the soluble solid concentrations (°Brix) decreased. The b value (yellowness) of Muscat of Alexandria wine was the highest at 8.31 in C treatment, which is a wine with a long maceration period, and B (7.19) and A (5.27) were significantly decreased as the maceration period was shorter. The total polyphenol and tannin content of wine increased with the period of maceration. Total polyphenol and tannin contents had the highest values (64.20 and 67.11 mg%, respectively) in the C treatment, which is a wine with a long maceration period on the 12th day of fermentation period. The physiological activities of Alexandria wine were highest level in the treatment with a long maceration period. As a result, this study provides useful scientific information that quality characteristics and physiological activities in white wine.

• The Korean Journal of Food And Nutrition
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• v.30 no.5
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• pp.889-899
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• 2017

To investigate the quality characteristics of domestic $ros{\acute{e}}$ wines marketed in Korea, 11 kinds of wines were purchased at the Korea Wine Festival in 2016. The color, physiological activity, aroma component and sensory evaluations were conducted. The hue value of $ros{\acute{e}}$ wines ranged from 0.592 to 1.990, with the Ro7 of Delaware having the highest value. The brightness of $ros{\acute{e}}$ wines ranged from 42.96 to 94.99, the redness from 3.20 to 59.37, and the yellowness from 8.43 to 24.83. Of the 11 $ros{\acute{e}}$ wines evaluated, 1 was a dry wine and 10 were sweet wines. The average sugar content of the sweet wines was 73.89 mg/mL. Among the organic acid contents, malic acid ranged from 0.214 to 2.903 mg/mL, and lactic acid content ranged from 0 to 3.423 mg/mL. Malolactic fermentation differed, depending on the source. The total polyphenol content of $ros{\acute{e}}$ wines ranged from 50.55 to 99.55 mg%, the anthocyanin content was 2.12 to 213.30 mg/L, and the DPPH radical scavenging activity of $ros{\acute{e}}$ wines was between 73.75 to 90.41%. A total of 41 volatile components were detected, including 7 alcohols, 22 esters, 4 terpenes, 3 acids and 5 other compounds. Of these, 9 compounds had odor activity value(OAV) greater than 1; these were identified as 1-propanol (alcohol, pungent), 3-methyl-1-butanol (harsh, nail polish), ethyl butanoate (strawberry, lactic), isopentyl acetate (fresh, banana), ethyl hexanoate (green apple, fruity), ethyl octanoate (pineapple, pear, floral), ethyl decanoate (fruity, fatty, pleasant), linalool (flower, lavender) and limonene (lemone, orange). As a result of the sensory evaluation, the Ro5 wine made from Campbell Early grape, and having a good color, flavor and taste, was the most preferred.

• Journal of the East Asian Society of Dietary Life
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• v.8 no.4
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• pp.462-468
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• 1998

편이었다. 미량성분으로는 K이 다량으로 존재하였고, 2단계 발효로 제조된 포도식초는 포도양파식초 보다K, Na, Cu함량이 높게 나타났다. ^x Grape vinegar (A) and grape onion vinegar(B) added (3% of onion juice) were produced through two stages of fermentation(alcohol fermentation and acetic acid fermentation) to increase the grape's use. Grape wine which contained 5.6% alcohol was produced on the 3rd day of first stage. Then through the second stages, grape vinegar, of which total acidity was 5.37% was produced. The quality of (A) and ( B) which was produced through the two stages of fermentation was compared with the traditional grape vinegar (C, D) in the market. The content of sugar in (D) was a little higher such as 5.4 $^{\circ}$Brix than others. That of (A) and (B) was 5.13, 4.98 $^{\circ}$Brix respectively. The content of remaining alcohol in (C) was high such as 0.23% comparatively. But there was no remaining alcohol in (A) and (B). The content of acetic acid was 4.3~5.3% as a major organic acid of vinegars. The content of tartaric acid was 340.0 in (A), 315.7 in (B), 322.6 in (C) and 391.7mg% in (D). The content of lactic acid was distinctly high such as 277.4mg% in (D) There were differences such as 9.2~15.5mg% in the content of total free amino acids among grape vinegars. (D) contained 15.5mg% of total free amino acid and (B) also highly such as 12.0mg%. Potassium was high in grape vinegars. The content of potassium, sodium and copper was higher in (A) than (B).