• Preventive Nutrition and Food Science
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• v.20 no.4
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• pp.292-297
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• 2015

The objective of this study was to compare the effects of adding lactic acid and pectinase, and chaptalization for the quality of apple wine and the production of hazardous compounds (methanol and acetaldehyde). The pH of all of the samples was below 4; therefore, mash seemed to be fermented without any issue. Total acidity was the highest in sample A due to lactic acid addition. Pre-treated groups (samples B, C, and D) showed higher total acidities than that of the control (P<0.05). Pre-treatments might influence the production of organic acids in apple wines. The control and pectinase added sample (sample B) had the lowest alcohol contents. Adding lactic acid produced more alcohol, and chaptalized samples produced more alcohol due to the addition of sugar. Adding pectinase with and without chaptalization was not effective for producing more alcohol. The control sample had significantly higher acetaldehyde content (2.39 mg/L) than the other samples (1.00~2.07 mg/L); therefore, pre-treatments for apple wine fermentation produced a lower amount of acetaldehyde. Among the pre-treated samples, samples C and D showed the lowest acetaldehyde content of 1.00 mg/L and 1.16 mg/L, respectively. On the other hand, a significantly higher amount of methanol was generated for sample A (1.03 mg/L) and sample D (1.22 mg/L) than that of the control (0.82 mg/L) (P<0.05). Adding lactic acid or chaptalization was effective in reducing methanol and acetaldehyde in apple wines.

• Journal of the Korean Society of Food Culture
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• v.9 no.4
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• pp.355-367
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• 1994

This study aims at exploring the nature of the traditional Korean wines brewed throughout the Southern Region of Korea-Chulla-do, Kyungsang-do and Cheju-do describing their varieties and brewing methods and also comparing the similarities and differences of their features. When compared with the wines produced in the Central Region, the Southern varieties are very fastidious and complex in their brewing methods, which in turn show a wide range of diversity. First of all, all the 29 kinds of wines investigated, not a single one shows any resemblance to any one of the remaining, each exhibiting peculiar and particular characteristic features of its own. Especially, the distilling methods demonstrate very complex processes. Secondly, the majority of the Southern spirits are made from grains, added with fragrant flavor of pine tree, wormwood, chrysanthemum leaves and other medicine herbs such as Chinese matrimony vine and tankui. Thirdly, they are brewed with yeast made from wheat into kodupap(steamed rice) type of spirits, emerging as in the form of blended liquor. Fourthly, in brewing, different fermenting temperature and duration are required. Typewise, the temperature required for the basic spirit is $15{\sim}20^{\circ}C\;or\;25{\sim}30^{\circ}C$ : in the case of blended secondarily fermented liquor, from the minimum of $0{\sim}5^{\circ}C$ to the maximum of $75{\sim}80^{\circ}C$. The brewing duration is $3{\sim}5$ days for the basic spirits. In some cases, from the minimum of 3 days to the maximum of 100 days are consumed for fermenting. Fifthly, the wine extraction gadgets are yongsu (wine strainer), the sieve, filter paper, Korean traditional paper, the utilization of which implies that the brewers endeavor to observe and preserve the traditional and indigenous methods of wine making.

• Korean journal of food and cookery science
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• v.29 no.1
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• pp.11-18
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• 2013

In this study, rice wine cakes (Jubak) was produced using with Astragali memvranaceus with excellent antioxidant and antidiabetic effects and produced. This Jubak was applied to improve the cookies of modern taste and well-being products. The cookies according to the different ratio (added 0-1.0%) of Astragali memvranaceus and investigated the physicochemical characteristics, sensory evaluation, DPPH free radical scavenging activities, polyphenol and flavonoid contents. There were little changes in pH and density. The hardness of all treated cookies increased with Astragali memvranaceus Jubak(AJ) containing of different moisture contents. In color, L and a values of most cases increased in most of the treatments, but b value was reduced. In the sensory evaluation, the flavor and total scores showed the highest in 0.5% AJ cookies. But the higher proportion of AJ cookies that had unique flavors and tastes, so the total acceptance score decreased. The polyphenol and flavonoid contents increased in the higher proportion of AJ. In DPPH free radical scavenging activities, the control (no Jubak added) was 44%, and containing of 1% AJ cookies showed 82%. In conclusion, our study suggests that 0.5% in addition of AJ increased positive attributes and functional to cookies.

• Proceedings of the Korean Society of Life Science Conference
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• 2006.09a
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• pp.75.1-75.1
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• 2006

• Journal of Life Science
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• v.21 no.4
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• pp.509-514
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• 2011

Maloactic fermentation (MLF) occurs after completion of alcoholic fermentation and is mediated by lactic acid bacteria (LAB), mainly Oenococcus oeni. Kiwi wine more than commercial grape wine has the problem of high acidity. Therefore, we investigated the optimal MLF conditions for regulating strong acidity and improving the quality properties of wine fermented with Kiwi fruit cultivated in Korea. For alcohol fermentation, industrial wine yeast Saccharomyces cerevisiae KCCM 12650 strains and LAB, known as MLF strains, were used to alleviate wine acidity. First, the various experimental conditions of Kiwi fruit, initial pH (2.5, 3.5, 4.5), fermenting temperature (20, 25, $30^{\circ}C$), and sugar contents (24 $^{\circ}Brix$), were adjusted, and after the fermentation period, we measured the acidity, pH, and the change in organic acid content by the AOAC method and HPLC analysis. The alcohol content of fermented Kiwi wine was 12.75%. Further, total acidity and pH of Kiwi wine were 0.78% and 3.5, respectively. Total sugar and total polyphenol contents of Kiwi wine were 38.72 mg/ml and 60.18 mg/ml, respectively. With regard to organic acid content, the control contained 0.63 mg/ml of oxalic acid, 2.99 mg/ml of malic acid, and 0.71 mg/ml of lactic acid, whereas MLF wine contained 0.69 mg/ml of oxalic acid, 0.06 mg/ml of malic acid, and 3.12 mg/ml of lactic acid. Kiwi wine had lower malic acid values and total acidity than control after MLF processing. In MLF, the optimum initial pH value and fermentation temperature were 3.5 and $25^{\circ}C$, respectively. Therefore, these studies suggest that establishment of optimal MLF conditions could improve the properties of Kiwi wine manufactured in Korea.

• Journal of Microbiology and Biotechnology
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• v.3 no.2
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• pp.108-114
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• 1993

A new strain of acidophilic, acetogenic bacterium, Acetobacter sp. strain HA was isolated by selective enrichment from the traditionally fermented rice wine vinegar in Korea. It was a gram-negative, non-motile short rod and oxidized acetate and lactate. The optimal temperature and pH for growth were $28^{\circ}C$ and 4.0, respectively. The strain HA differed from other Acetobacter species by growing well on methanol, xylitol, inositol, dulcitol, D-xylose, L-arabinose, and D-mannose as sole sources of carbon and energy. The isolated strain HA did not produce $\gamma$-pyrones from glucose and did not produce ketone bodies from glycerol. The quinone system used in this study was an ubiquinone-9 isoprene unit. The guanine-plus-cytosine content of the DNA was 50.7 mol%, and the major cellular fatty acids were $C_{18:1} and C_{16:0}$.

• Journal of the Korean Society of Food Science and Nutrition
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• v.28 no.2
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• pp.353-358
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• 1999

We produced the apple vinegar with only apple fruits, no adding sugar and others through two stages fermentation(alcohol fermentation and acetic acid fermentation). At the first stage, apple wine contained 5% alcohol was produced at the 5th day. And through the second stage, acetic acid fer mentation, apple vinegars of which total acidity is 5.88% were produced. In comparision with com mercial vinegars for physicochemical quality, it was the lowest in total acidity. But contents of oxalic, tartaric, malic, citric, succinic acid in it were higher than other vinegars. Especially the content of malic acid in it was higher 5 times than other vinegars. Malic acid was known that it was abundant in apple fruits. Also the contents of free amino acids were distinctly high such as 21.97mg% in two stages fermented apple vingars. Potassium content in it was higher 4 times than other vinegars. So it was supposed that two stages fermented vinegar had much higher quality than commercial vinegars.

• Korean Journal of Food Science and Technology
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• v.40 no.1
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• pp.63-69
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• 2008

For the development of mulberry wine, we investigated its optimum fermentation conditions as well as quality changes during fermentation. The physicochemical characteristics of the mulberry fruit used in the study were pH 4.56, 0.50% titratable acidity, and 13.0 $^{circ}Brix$ soluble solids. The mulberry wine fermented with Saccharomyces cerevisiae KCCM 12224 (Sc-24) at 24 $^{circ}Brix$ soluble solids and $26^{circ}C$ showed excellent characteristics in terms of ethanol production, titratable acidity, and redness. The sucrose, fructose, and glucose contents of the mulberry wine drastically decreased with fermentation time. The citric acid content was maintained during the fermentation period, and malic acid decreased, but lactic and succinic acids increased. The cyanidin-3-glucoside content, a major anthocyanin pigment, of the mulberry wine drastically decreased from 195.5 mg% at the initial stage of fermentation to 15.37 mg% at 2 days of fermentation. However, cyanidin-3-rutinoside decreased gradually. In summary, a mulberry wine of high quality was made by fermentation for 8 days at $26^{\circ}C$ using mashed mulberry fruit containing $24^{\circ}Brix$ soluble solids, after adding 200 ppm $K_2S_2O_5$ and inoculating with 3%(v/v) Sc-24.

• Food Science and Preservation
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• v.21 no.5
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• pp.757-765
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• 2014

Campbell Early grapes were spontaneously fermented with and without sulfiting to investigate the effect of sulfiting on the fermentation characteristics and physicochemical properties of Campbell Early wine. During the fermentation, the increase in the alcohol and the decrease in the soluble solid contents were faster without sulfiting, as was the increase in the yeast viable counts compared to those with sulfiting. However, the final alcohol and soluble solid contents reached similar levels with and without sulfiting. The PCR-RFLP analysis of the yeast in the ITS I-5.8S-ITS II region revealed that the increase in the S. cerevisiae was faster in the initial fermentation stage and reached a slightly higher level in the late stage with sulfiting than without sulfiting. The wine prepared after the fermentation with sulfiting showed higher malic and tartaric acid contents, as well as methanol, acetaldehyde, and n-propanol contents, than the wine prepared without sulfiting. The ethyl acetate content of the wine without sulfiting was 375.5 mg/L, which was 5.3 times higher than that (70.5 mg/L) with sulfiting. In the sensory evaluation, the wine without sulfiting obtained higher scores in flavor and overall preference than that with sulfiting.

• 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.