• Korean Journal of Food Science and Technology
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• v.20 no.5
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• pp.718-723
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• 1988

A yeast strain producing fruity-floral aroma was isolated from soil and identified as Hansenula saturnus var. saturnus. Glucose was found to be the best carbon source and sodium nitrate or phenylalanine as nitrogen source in terms of the nature and the intensity of the aroma produced by the isolated yeast. Seventeen compounds, mainly esters and alcohols, were identified in the ether-pentane extract of the culture broth by gas chromatography and/or coupled gas chromatography-mass spectrometry. Ethyl alcohol, isobutyl alcohol, isoamyl alcohol, phenethyl alcohol and their acetate esters together with ethyl caprylate were the major compounds in the aroma concentrate. Three unusual compounds, dibutyl disulfide, 3-methyl pentanoic acid and methyl pentanoate were also tentatively identified in the culture broth of the isolated yeast.

• Food Science and Preservation
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• v.3 no.2
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• pp.179-185
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• 1996

This study was carried out for the purpose of improving the persimmon vinegar. Crushed persimmon(persimmon pulp) was used at alcohol fermentation using Saccharomyces bayanus for persimmon alcohol medium preparation. Glucose(8.39%) and fructose(7.96%) were the dominant free sugar in persimmon pulp before the at cohol fermentation. They decreased abruptly during alcohol fermentation and glucose was consumed more rapidly than fructose. Final alcohol concentration was finally reached to 8%(v/v) in 5 days for mentation of persimmon pulp. Pectinase pre-treatment of persimmon pulp resulted in tusker contents of galacturonic acid, galactose, methyl alcohol and isoamyl alcohol in main mash for alcohol fermentation than those in main mash prepared without pectinase pre-treatment. After alcohol fermentation tannin concentration was 350ppm and astringency was not perceived.

• Food Science and Preservation
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• v.19 no.3
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• pp.433-437
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• 2012

The fusel oils and the volatile flavor compounds of two potato sojues, one of which was produced with the traditional distillation apparatus(soju-gori) and the other, with the reduced pressure distillation system, were examined. The fusel oil content was high in the potato soju that was distilled under reduced pressure (potato soju(II)). The relative ratio of the isoamyl alcohol to the isobutyl alcohol and the n-propanol was 3.1:0.8:1.0 in the potato soju that was distilled with soju-gori (potato soju(I)), and 4.0:1.2:1.0 in potato soju(II). The chromatograms of the volatile components apparently differed between potato soju(I) and potato soju(II). Potato soju(I) contained four kinds of alcohol, six kinds of ester, n-valeraldehyde, and acetic acid. Potato soju(II) contained seven kinds of alcohol, 14 kinds of ester, two kinds of aldehyde, acetic acid, and three other compounds. Potato soju(II) significantly scored higher for flavor property than potato soju(I).

• Mycobiology
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• v.45 no.2
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• pp.119-122
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• 2017

Herein, nuruks derived from non-glutinous and glutinous rice inoculated with Aspergillus oryzae N159-1 (having high alpha-amylase and beta-glucosidase activities) were used to produce Korean alcoholic beverages. The resultant beverages had enhanced fruity (ethyl caproate and isoamyl alcohol) and rose (2-phenethyl acetate and phenethyl alcohol) flavors and high taste scores.

• Food Science and Preservation
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• v.18 no.5
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• pp.779-785
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• 2011

This study was conducted to investigate and compare the characteristics of alcohol fermentation in oriental melon by different yeast. As a result, no significant difference in pH, total acidity and sugar content was found in alcohol fermentation of oriental melon by different yeast. The pH was shown to be constantly maintained but the total acidity was shown to increase during fermentation process. The sugar content was rapidly decrease starting from 3 day of fermentation, and it was reduced to be approximately 7 oBrix after fermentation. For organic acid content, lactic and citric acid contents were shown to be the highest in all periods of fermentation, which revealed that lactic and citric acid were major organic acids. Free sugar content were shown to gradually decrease during the fermentation and to be rarely detected at 9 days of fermentation. Alcohol content was shown to be 14.20% at (C) S. cerevisiae RC-212, which was the highest content. It was shown to be more than 12% at other periods, which showed that no significant difference in alcohol content was found according to different yeast. For alcohol components, acetaldehyde content was shown to be the highest at (E) S. cerevisiae K1-V1116, and methanol content was shown to be relatively higher at (C) S. cerevisiae RC-212 and (D) S. bayanus EC-1118. N-propanol, 2-methyl-1-propanol and isoamyl alcohol, which belong to fusel oil, were shown to be produced at 3 day of fermentation and gradually increase. These results, no significant difference in physicochemical properties of alcohol fermentation in oriental melon by different yeast.

• Food Science and Preservation
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• v.17 no.5
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• pp.616-624
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• 2010

We compared the physicochemical properties of, and volatile components in various commercial fruit vinegars (made from apples, grapes, and persimmons). Total acidity was highest in grape vinegars. Significant between-sample differences were evident in total and reducing sugar contents. Brownness, turbidity, and overall color difference (the ${\Delta}E$ value) were highest in persimmon vinegars. Free sugars were composed mainly of fructose, glucose, sucrose, and maltose. Major organic acids were present in the (descending abundance) order acetic acid, oxalic acid, citric acid, malic acid, and succinic acid, among-samples difference were negligible. Nine-essential free amino acids were detected in nine types of grape and persimmon vinegars, and in six varieties of apple vinegar. Among 17 types of volatile compounds identified in apple vinegars, 12 in grape vinegars, and 33 in persimmon vinegars, the main volatile components were acetic acid, ethyl acetate, isoamyl acetate, isovaleric acid, isoamyl alcohol, propanoic acid and phenethyl acetate. Volatile chemicals in commercial fruit vinegars were effectively analyzed using a SAW e-nose.

• Applied Biological Chemistry
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• v.46 no.3
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• pp.207-213
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• 2003

Kochujang was prepared for this study with raw material inoculated by commercial enzyme of amylase and protease. Volati1e compounds of Kochujang were analyzed using a purge and trap method during fermentation and identified with GC-MSD. Total 54 kinds of volatile flavor components like 16 kinds of alcohol, 16 kinds of ester, 7 kinds of acid, 4 kinds of aldehyde, 2 kinds of alkane, 1 kind of benzene, 3 kinds of ketone, 1 kind of alkene, 2 kind of amine, 1 kind of phenol, other 1 were found. Total number of volatile flavor detected right after manufacturing were 23 kinds like 3 kinds of alcohol, 6 kinds of ester, 3 kinds of aldehyde. After 30 days storage, total number of volatile flavor went up to 31 kinds with addition of 4 kinds of alcohol, 1 kind of ester. The total number of volatile flavor after 120 days storage were increased to 49 kinds. Volatile flavor compounds detected during the storage period were total 20 kinds like 6 kinds of alcohol such as 2-methyl-1-propanol, ethanol, 3-methyl-1-butanol, 5 kinds of ester such as ethyl acetate, isoamyl acetate, ethyl butyrate, 3 kinds of aldehyde such as butanal, acetaldehyde and 6 kinds of others. Even though peak area % of flavor compound varied depends on fermentation period, ethanol, ethyl acetate, ethyl butyrate, ethenone, 2-methyl-1-propanol, 3-methyl-1-butanol were the main compounds that consisted of flavor from Kochujang which was made with enzyme treatment. Ethly acetate showed the highest result in the treatment of right after manufacturing, 3-methyl-1-butanol had up to 90th day and ether were the other days.

• Korean Journal of Food Science and Technology
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• v.41 no.5
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• pp.503-508
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• 2009

The principal objective of this study was to evaluate the physicochemical properties and volatile compound contents of Moju acquired from 12 restaurants in Jeonju. The alcohol contents were lower than 2.1%, and the pH values ranged from 3.85 to 4.38. Total acidity, $^{\circ}Bx$, and UV absorbance values differed among the samples according to the type of side materials added. Reducing sugar contents were found to be substantially superior to other commercial takju variants. Malic and lactic acid contents were higher than the contents of other organic acids, and the free sugar contents were as follows: maltose>glucose>fructose. Overall, the high b (yellowness) and cP values were attributable to the turbid yellow and heavy condition of the samples. The volatile compound contents of Moju were analyzed via GC and GC/MSD. 30 components were identified, including 3 alcohols, 12 esters, 7 hydrocarbons, and 4 aldehydes. Among the alcohol compounds, benzeneethanol levels were higher than the levels of isoamyl alcohol. Ethyl caprate, ethyl palmitate, and ethyl linoleate, which were fundamentally attributable to origin liquor, were highest among the 12 esters. (E)-cinnamaldehyde, which was the most abundant among 7 hydrocarbons, and (E)-cinnamyl acetate contents were attributed to the presence of cinnamon, a common supplement in the processing of Moju.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.8
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• pp.637-645
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• 2016

This study was conducted to investigate the characteristics of fermentation and quality of Cheongju prepared by mashing using rice Nuruk inoculated with Aspergillus oryzae. Mashes were prepared by fermentation for 30-50 days using different amounts of fermenting agent, brewing water, milling ratios and fermenting temperatures. Adding fermenting agent at 15% resulted in slow fermentation, but a final alcohol content of 17% (v/v), similar to other samples tested. Addition of higher amounts of Nuruk resulted in increased amounts of citric acid, tartaric acid and malic acid, but low levels of succinic acid. Incomplete fermentation occurred when the ratio of brewing water was low, but the alcohol content (17%) of all samples was similar. When the amount of brewing water was high, the organic acid was levels were high. The speed of saccharification and fermentation was low when fermentation was conducted at $10^{\circ}C$, but the final alcohol content was the highest at this temperature. However, the content of n-propanol, isobutanol, isoamyl alcohol and organic acid was low at low temperature. At this time, the content of citric acid and malic acid was low, but the content of succinic acid was high. A higher milling degree resulted in a lower content of alcohol, organic acid and higher alcohols, with 10% milling resulting in a significantly higher content than the other samples.

• Korean Journal of Food Science and Technology
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• v.46 no.4
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• pp.425-431
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• 2014

In this study, the volatile compounds in 24 commercial Korean black raspberry wines were isolated by headspace solid-phase microextraction and analyzed by gas chromatography-mass spectrometry (GC-MS). A total of 43 volatile components, including 15 esters, 12 terpenes, 7 alcohols, 4 acids, 3 ketones, and 2 aldehydes, were identified. Ethyl esters and alcohols such as ethyl acetate, ethyl octanoate, isoamyl alcohol, and phenethyl alcohol were the most represented groups among the quantified volatiles. In particular, various terpenes such as DL-limonene, linalool, alpha-terpineol, and myrtenol were identified. The differences in volatile components among the 24 black raspberry wines and possible sample grouping were examined by applying principal component analyses to the GC-MS data sets. The first and second principal components explained 43.9% of the total variation across the samples. No apparent sample groupings were observed according to manufacturing locations. The samples KU, BH, SR, and MO showed higher overall levels in the concentrations of terpenes originating from black raspberry, while other samples such as BB and HB, showed higher in ethyl ester and alcohol contents produced by yeast fermentation, respectively.