• Microbiology and Biotechnology Letters
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• v.39 no.2
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• pp.153-160
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• 2011

In this study, we have developed taste and other functional enhancements of yam chips, from tasteless and flavorless yam slices, through the process of soaking freeze-dried yam in different commercially available juices, including apple, omija (fruit of Maximowiczia typica), grape, wild grape, orange, tomato, red ginseng, and black garlic juice. The analyses of color (brightness, redness and yellowness), pH, brix, acidity, total polyphenol, total flavonoids, total sugar and reducing sugar, DPPH and ABTS scavenging activity, reducing power and nitrite scavenging activity, of the different yam chips showed that the freeze-dried yam slices absorb various components of fruit juices, such as flavonoids, sugars, organic acids and flavors, during the soaking process. These changes resulted in increased taste (both sweet and sour tastes), flavor and antioxidant activity in the yam chips. The soaking time for yam slices in juice is considered to be a crucial factor for the taste and bioactivity of yam chips. In the case of grape juice-yam chips, which had the highest preference among the 8 different chips, the optimum soaking time was noted as 120 seconds. The optimization of the soaking process is necessary for various juices. These results suggest that taste, and other functional enhancements, in yam chips can be developed by juice-soaking and freeze-drying methods.

• Korean Journal of Food Science and Technology
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• v.25 no.2
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• pp.98-104
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• 1993

In order to improve qualities of kochujang, various fruit juices such as apple, orange, pineapple and grape were added to the raw material of kochujang instead of the part of water. It was apparent in the kochujang with pineapple juice that organic acids originated from fruit juices increased titrable acidity and decreased pH. Free sugars and organic acids in the kochujang that was fermented during three months were degraded or might be used by microorganism after ten months of fermentation. Kochujang with grape juice showed relatively dark color, which had a good agreement with the changes of Hunter a-value. Sensory evaluation test about tastes, flavor and color showed that the kochujang with pineapple juice was preferred to others.

• KSBB Journal
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• v.31 no.1
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• pp.8-13
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• 2016

Excessive alcohol consumption can cause hangover symptoms, such as headache, drowsiness, dizziness, gastrointestinal distress, and anxiety. The aim of this study was to investigate alcohol metabolizing enzyme activities and antioxidant activities of fruit-vegetable juices containing Angelica keiskei prepared using a low speed masticating juicer in vitro. The acceleration rate of alcohol dehydrogenase (ADH) by A. keiskei-cherry tomato juice (ACJ) and A. keiskei-green grape juice (AGJ) were $163.8{\pm}4.3%$ and $148.2{\pm}6.9%$, respectively. The acceleration rate of aldehyde dehydrogenase (ALDH) by ACJ and AGJ were $185.6{\pm}9.5%$ and $161.1{\pm}4.8%$, respectively. Total polyphenol of ACJ and AGJ were $111.1{\pm}1.6mg/dL$ and $100.8{\pm}2.9mg/dL$, respectively. DPPH radical scavenging activities of ACJ and AGJ were $62.0{\pm}0.5%$ and $61.3{\pm}0.4%$, respectively. Thus, these results indicate that alcohol degrading enzyme activities can be enhanced by fruitvegetable juices containing A. keiskei.

• Korean Journal of Food Science and Technology
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• v.29 no.3
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• pp.571-575
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• 1997

In the present study, characterization of fermented carrot juice by Bifidobacterium was performed. When inoculated at the level of $10^6\;CFU/mL$ with various Bifidobacterium strains, cell growth of B. longum, B. adolescentis and B. infantis reached more than $10^8\;CFU/mL$. On the other hand, B. bifidum strains reached less than $10^8\;CFU/mL$. Compared with carrot, grape juice did not allow the growth of Bifidobacterium, while peach juice and orange juice were as good as carrot for the growth of Bifidobacterium. On mixed culture with Lactobacillus, growth of Bifidobacterium decreased and cell death rate increased considerably. On panel test, Bifidobacterium cultured-carrot juice showed high score on sensory test than non-fermented carrot. Therefore, fermentation may lead to the quality improvement of carrot juice by combining health-promoting effect of Bifidobacterium and high nutrition value of carrot.

• Journal of Ginseng Research
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• v.33 no.4
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• pp.349-354
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• 2009

This study was conducted to develop a new method for enhancing ginsenoside $Rg_3$, which is abundant in black ginseng. The cognition-enhancing effect of black ginseng extract was investigated via the assay of acetylcholinesterase (AChE) activity. Black ginseng I was prepared through the traditional method (by steaming and drying nine times repetitions). Black ginseng II, on the other hand, was prepared by steaming the ginseng three times at $120^{\circ}C$ for 30 min after soaking it in grape juice for 24 h. The ginsenosides of white, red, and black ginseng I, and II were investigated using the HPLC method, respectively. In black ginseng II, the ginsenoside $Rg_3$ contents, which cannot be found in white ginseng, amounted to 10.91 mg/g, approximately 18 times more than that in red ginseng. In the in-vivo study, black ginseng extract (200 mg/kg, p.o.) inhibited the AChE activity after 24 h by a single administration in the brain. Thus, the new manufacturing method for black ginseng was found to more effective in the conversion of ginsenoside $Rg_3$ compared to the traditional method. Black ginseng may also have the effect of preventing the cognitive impairment induced by cholinergic dysfunction.

• 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.

• Food Science and Preservation
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• v.17 no.6
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• pp.807-813
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• 2010

Muscat Bailey A grapes, one of the major grape varieties in Korea, contain 18-20% (w/w) sugars, which is less than the amount required to make red wine. In the present study, fermentation of freeze-concentrated Muscat Bailey A grape juice to $24^{\circ}Brix$ was performed using several industrial wine yeasts, including Saccharomyces cerevisiae $OC_2$, S. cerevisiae Fermivin and S. cerevisiae W-3. During fermentation, changes in the levels of soluble solids, alcohols, and yeast viable counts were monitored. Wine quality parameters including organic acid, minor alcohol, sensory score, etc. were also analyzed. Alcohol contents reached maximal levels after 9 days of fermentation, and were 12.6% (v/v) when Fermivin was used and 13% (v/v) when strains $OC_2$ and W-3 were used. No major difference between strains was apparent, except that Fermivin fermentation was somewhat slower in terms of both alcohol production and sugar consumption. Similar levels of soluble solids and total phenols were measured in wines fermented by each of the three strains. The total acid level of W-3 wine was high, whereas the alcohol content of Fermivin wine was low. Although the wines were variable in terms of acetaldehyde and minor alcohol contents, the levels of these materials were much lower than the limits set by the Korean National Tax Service. Upon sensory evaluation, $OC_2$ wine obtained the highest scores in terms of color, flavor, and overall acceptance. However, the best taste score was awarded to the Fermivin wine, which had the same flavor score as $OC_2$ wine but a slightly lower overall acceptance score.

• The Korean Journal of Food And Nutrition
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• v.32 no.5
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• pp.485-493
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• 2019

The purpose of this study was to investigate the quality characteristics and volatile flavor components of Doonuri wine, using freeze concentration. The freeze concentration can increase the sugar concentration in grape juice by reducing its water content. In this study, after eight days od fermentation, the alcohol content of freeze-concentrated Doonuri wines was 12.5~14.1%. The pH of the wine was 3.42~3.50 and the total acid content was 0.68~0.94 g/100 mL, respectively. The brghtness of freeze-concentrated Doonuri wines was 19.28~54.42, the redness was 41.98~49.58, and the yellowness was 36.16~42.36. The organic acid analysis of Doonuri wines was that most of the organic acids contain tartaric and malic acid. By using freeze concentration with grape juice, significant increase in the total polyphenol content of Doonuri wines was 122.40~137.26 mg/mL, the total anthocyanin content was 117.06~118.40 mg/L and the tannic acid content was 66.23~83.70 mg%. In GC/MS analysis, the volatile flavor component analysis of Doonuri wines identified six alcohols, five esters, two ketones, on acid, two alkanes, and four other compounds.

• Applied Biological Chemistry
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• v.18 no.4
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• pp.219-227
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• 1975

In order to investigate the possibility of wine-making with the grape variety cultivating in Korea, the basic analysises were carried out; analysis of the grape maturity during ripening period, the composition of grape juice, and the chemical components of wine from different varieties. Also the yeasts existing naturally on the grape were isolated and identified. For the selection of strain, the characteristics of 6 strains were studied. The results obtained were summarized as follows. 1. The reducing sugar content increased considerably during two weeks after the ordinary grape-gathering period. 2. The sugar content was highest in Muscat bailey A, which could be fermented naturally. The other varieties, Campbell Early, Steuben, and Alden needed chaptalisation for wine-making. 3. The permanaganate number and the methanol content of wine from all varieties were lower than french wine. 4. The sensory evaluation of wine showed that the pink wine was appreciated better than the red wine of same variety and the foxy taste of wine from hybrid grape influenced little to Korean. 5. The selected 6 strains were identified as Saccharomyces chevaliers, Saccharomyces capensis and Saccharomyces globosus. The strain No. 3 and No. 4 showed the most excellent characters for wine-making.

• Journal of Food Hygiene and Safety
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• v.25 no.4
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• pp.281-288
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• 2010

Total aflatoxin ($B_1+B_2+G_1+G_2$) maximum levels of 15 ${\mu}g/kg$ ($B_1=10\;{\mu}g/kg$) were set for grain, beans, peanut, nuts & their processed food (grinding, cutting etc.), processed cereal product & processed bean product, confectionaries (peanut or nut-containing food), soybean paste, red pepper paste, dried red pepper, processed com products for popcorn and steamed rice. The maximum levels for aflatoxin $M_1$ are 0.5 ${\mu}g/kg$ for raw milk and milks before manufacturing processing. The patulin maximum level is 50 ${\mu}g/kg$ in apple juice and apple juice concentrate (including concentrate to use as raw material and converted by concentration multiple). The ochratoxin A is managed at the maximum levels of 5 ${\mu}g/kg$ in wheat, barley, rye, coffee beans and roasted coffee, 10 ${\mu}g/kg$ in instant coffee and raisin, 2 ${\mu}g/kg$ in Grape juice, concentrated grape juice as reconstituted and wine. The fumonisins ($B_1+B_2$) maximum levels are 4000 ${\mu}g/kg$ in com, 2000 ${\mu}g/kg$ in com processed food (grinding, cutting etc.) and com powder, 1000 ${\mu}g/kg$ in processed com products. Standards for mycotoxins in food have been established and the mycotoxin risk in food is managed reasonably and scientifically, based on risk assessment and exposure analysis.