• Korean Journal of Food Science and Technology
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• v.30 no.3
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• pp.638-643
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• 1998

The volatile flavor components in Takju made from mashed glutinous rice and barley rice were identified by GC and GC-MS using polar column. Twenty eight kinds of flavor compounds including 10 alcohols, 9 esters, 2 acids, 7 aldehydes were identified. At the beginning of fermentation 14 kinds of volatile components were detected and the kinds of volatile components were increased up to maximum after fermentation for 16 days. The contents of volatile components in the sample made from glutinous rice contained slightly higher than the sample made from barley rice. Ethyl alcohol, n-propyl alcohol, iso-amyl alcohol, n-hexyl alcohol, hexenyl alcohol, 2-phenylethyl alcohol, ethyl acetate, ethyl succinate, 2-phenylethyl acetate, butyic acid, benzaldehyde and 3-methoxybenzaldehyde were detected in the both of the sample throughout the fermentation process. Five kinds of aldehyde including ethyl propionate, iso-amyl acetate, ethyl caprylate and ethylphenyl acetate were detected only in the sample fermented for 16 days. The main components of the both sample were ethyl alcohol, iso-amyl alcohol, 2-phenylethyl alcohol, 2-phenylethyl acetate, hexenyl alcohol and iso-butyl alcohol. Besides ethyl acetate and benzaldehyde from glutinous rice Takju and hexenyl alcohol from barley rice Takju were found as main components.

• Journal of the Korean Society of Food Science and Nutrition
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• v.24 no.6
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• pp.956-963
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• 1995

Twenty esters, 14 alcohols, 5 aldehydes, 5 ketones, 5 lactones, 2 S-containing compounds and 1 hydrocarbon are identified by GC-MS from volatile compounds in a glucose solution containing Yeat-Carbon-Base medium fermented for 64 hrs by Saccharomyces bayanus at pH 3.5, $25^{\circ}C$, 400rpm and 35L/h of aeration for 24hrs. Under the different conditions of conservation(1~4), ethyl 2-hydroxy-4-metjhylpentanoate, ethyl succinate, nonanol and phenylacetaldehyde are produced during conservation of fermented solution. 17 esters increased during conservation at $13^{\circ}C$ for 12 weeks and the increase of ethyl 9-hexadecenoate is important among 13 esters increased during conservation at $35^{\circ}C$ for 24hrs. During conservation, aldehydes increased at $35^{\circ}C$, but decreased at $13^{\circ}C$ and the great increase of isobutanal, benzaldehyde and phenylacetaldehyde is observed at $35^{\circ}C$. Alcoho and lactones increased but ketones decreased during conservation.

• Korean Journal of Food Science and Technology
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• v.42 no.5
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• pp.527-532
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• 2010

The properties of volatile flavor components were compared in commercial brown rice vinegars that were fermented with and without ethanol addition, for which solid phase microextraction-gas chromatography (SPME-GC), electronic nose, and sensory evaluations were performed. A total of 24 volatile compounds, mainly composed of acetic acid, ethyl acetate, benzaldehyde, iso-valeric acid, phenylethyl alcohol, 2-phenylethyl acetate, acetoin, and isobutyric acid, were identified in the brown rice vinegar fermented without ethanol, while major volatiles in the brown rice vinegar fermented with ethanol were acetic acid, ethyl acetate, 1-hexyl acetate, benzaldehyde, 2-phenylethyl acetate, and phenylethyl alcohol. The electronic nose patterns of samples indicated a significant difference in the brown rice vinegars fermented with and without ethanol. Pungent flavor and off-flavor intensity were high in the brown rice vinegar fermented without ethanol. According to the results, fermentation conditions affect the volatile properties of brown rice vinegars.

• Toxicological Research
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• v.31 no.3
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• pp.289-297
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• 2015

Ethyl carbamate (EC) classified as a probable human carcinogen (Group 2A) is naturally formed in alcoholic beverages and fermented foods during fermentation process and/or during storage. The objective of this study was to analyze EC in 34 food items including 14 alcoholic beverages and 20 fermented foods sold in Korea. Each food was collected from 18 supermarkets in 9 metropolitan cities in Korea, and then made into composite. According to food composition and alcohol content, samples were divided into four matrices such as apple juice, milk, Soju (liquor containing about 20% alcohol), and rice porridge. The maximum EC value of $151.06{\mu}g/kg$ was found in Maesilju (liquor made from Maesil and Soju). Whisky and Bokbunjaju (Korean black raspberry wine) contained $9.90{\mu}g/kg$ and $6.30{\mu}g/kg$, respectively. EC was not detected in other alcoholic beverages. Of 20 fermented foods, Japanese-style soy sauce had highest level of $15.59{\mu}g/kg$ and traditional one contained $4.18{\mu}g/kg$. Soybean paste had $1.18{\mu}g/kg$, however, EC was not found in other fermented foods.

• Korean Journal of Food Science and Technology
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• v.44 no.6
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• pp.779-784
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• 2012

Characteristic chemical compositions of jujube wine using different preparation methods including fermentation were investigated. Fermentation for jujube wine started using whole fruit (JW1), seed-removed fruit (JW2) and whole fruit heated at $100^{\circ}C$ for 2 h and then extracted (JW3). The free amino acids and flavors were analyzed quantitatively by HPLC and GC-MS. A total of 18 amino acids were identified in all samples. The amount of total free amino acids was detected from 141-210 ppm (JW1), 147-342 ppm (JW2), and 336-362 ppm (JW3). Large amounts of proline, aspartate, glutamate, arginine and alanine were detected in jujube wine. Thirteen kinds of volatile compounds including six alcoholic compounds (ethyl alcohol, iso-butyl alcohol, n-butyl alcohol, iso-amyl alcohol, n-amyl alcohol, and phenethyl alcohol), four ester (ethyl acetate, hexyl acetate, ethyl caprylate, and phenethyl acetate) and three aldehydes (diethylacetal, furfural, and benzaldehyde) were detected. Ethyl alcohol (30.50-33.95% peak area), benzaldehyde (2.55-15.97% ratio), furfural (0.07-15.28% ratio), iso-amyl alcohol (1.04-14.73% ratio), and phenethyl acetal (0.78-9.28% ratio) were abundant in jujube wine.

• Korean Journal of Food Science and Technology
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• v.41 no.1
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• pp.50-56
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• 2009

This study was carried out to determine the optimum extraction conditions for Ishige okamurai by comparing the yields, total phenolic compound content (TPC), and antioxidant properties of its 95%, 70%, 50% fermented ethyl alcohol and water extracts. Additionally, the effects of heat and pH treatments on the antioxidant properties of the extracts were evaluated by their TPC and 1,1-diphenyl-2-picrylhydrazyl(DPPH) radical scavenging capabilities. The yields of the extracts were greatest in the order of water > 50% > 70% > 95% fermented ethyl alcohol, and the TPC of the 70% (26.18%) and 50% fermented ethyl alcohol (27.56%) extracts were higher than those of the others. However, in terms of DPPH radical scavenging and ferrous-reducing power, the 70% fermented ethyl alcohol extract of Ishige okamurai showed the highest antioxidant effects. Additionally, in the results for the heat and pH treatments, the antioxidant properties of the 70% fermented ethyl alcohol extract were not influenced by the treatment conditions except at pH 10.

• Journal of the Korean Society of Food Science and Nutrition
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• v.32 no.7
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• pp.1011-1020
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• 2003

The present study was conducted to examine sensory characteristics of non-fermented tea and fermented teas with fermented times of 0 hr (green tea), 10 hrs (mild fermented tea), 17 hrs (medium fermented tea), 24 hrs (black tea), respectively. The lightness of tea powder and tea extract got lower, and the redness and the yellowness of those got higher as tea was more fermented. The result of sensory evaluation about the extracts of non fermented tea and fermented teas showed that the preference of flavor got higher in the more fermented tea but one got lower in a mild fermented tea according to temperatures, respectively. The preference of taste got higher at 60∼7$0^{\circ}C$ extracts in the green tea and got the highest at 80∼9$0^{\circ}C$ extracts in the medium fermented tea and black tea. A total of 76 flavor components was detected in non fermented tea and the total contents of those were 129.9 mg/kg. The major components were linalool, geraniol, nerolidol, benzyl alcohol, and linalool oxide. A total of 76 flavor components was detected in the mild fermented tea and total contents of those were 159.1 mg/kg. The major components were geraniol, linalool, linalool oxide, ethanol, benzyl alcohol, etc and were similar in those to the non fermented tea. A total of 79 flavor components was detected in the medium fermented tea and total contents of those were 455.6mg/kg. The major components were ethyl acetate, 3-methylbutanal, ethanol, (E)-2-hexenal, geraniol, linalooloxide. A total of 79 flavor components was detected in the Black tea and total contents of those were 680.5 mg/kg. The major components were 3-methylbutanal, ethyl acetate, geraniol, ethanol, (E)-2-hexenal, hexanal, linalooloxide. The amounts of flavor components was increased, but the amounts of aldehyde compounds was remarkably increased according to the degree of fermentation.

• Journal of the Korean Society of Food Science and Nutrition
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• v.23 no.3
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• pp.481-489
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• 1994

Volatile flavor compounds in low salt-fermented anchovy pastes by adding koji(Koji), compared with Control, were analyzed by simultaneous steam distillation -solvent extraction /gas chromatography/mass spectrometry. Volatile compounds (106) were detected inboth samples during fermentation. Among these, 79 compounds were positively identified and were composed mainly of aldehydes, esters, alcohols, ketones, nitrogen-containing compounds, aromatic hydrocarbons, and furans. Aldehydes and esters were found higher amounts that other compounds in both samples. Alkylpyrazine, such as 2, 6-dimethylpyrzine, 2-ethyl-6-methylpyrazine, trimethylpyrazie, 2-ethyl-3, 5-dimethylpyrazine and tetramethylpyrazine, and also 2-phenylethanol were identified only in Koji.

• Journal of Practical Agriculture & Fisheries Research
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• v.25 no.1
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• pp.20-35
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• 2023

Chemical preservatives have a good effect on antibacterial activity, but many side effects on the human body have been reported. Recently, the development of natural preservatives that are harmless to the human body and have preservative functions and self-efficacy is active. In addition, in order to increase the absorption rate of natural products by the human body, the method of fermentation using strains is also increasing. Therefore, this study selected varieties that are harmless to the human body and have good antibacterial activity. 1. The yield of origin, thickness and solvent was investigated. Scutellaria baicalensis Georgi was made in China and received a yield of 21.88% from 50% ethyl alcohol extract. Salvia miltiorrhiza Bunge was made in Korea and received a yield of 25.62% from 50% ethyl alcohol extract. Dryopteris crassirhizoma Nakai was made in China and received a yield of 6.50% from 70% ethyl alcohol extract. 2. The solid fermentation with the S. baicalensis and S. miltiorrhiza with B. Subtilis yield gained 24.40%, 39.30%, and D. crassirhizoma obtained 11.10% yield when fermented with L. casei. 3. After the liquid fermentation, a clear zone of 9mm was identified for the S. aureus strain in the S. baicalensis, and the antibacterial activity was not confirmed in S. miltiorrhiza and D. crassirhizoma. 4. When the S. baicalensis was fermented with L. Casei, it showed high antibacterial activity in C. albicans and S. aureus. S. miltiorrhiza showed antibacterial activity in S. aureus when it was solid with S. cerevisiae. When the spectators were solid with L. casei and S. cerevisiae, antibacterial activity was high in E. coli and S. aureus. Overall, the antibacterial activity after fermentation was much higher than when fermented. 5. The change in active ingredients was baicalin 101.57, baicalein 28.26, and wogonin 5.33mg/g in the S. baicalensis that did not ferment solid. When solid fermentation with S. cerevisiae, the content of baicalinin with baicalin 94.31, baicalein 30.41, and wogonin 3.57mg/g was found to have increased. S. miltiorrhiza that was not fermented, salvianolic acid A was 1.82mg/g, and when fermented with S. cerevisiae, it increased to 5.70mg/g. The active ingredients of the spectators were flavaspidic acid AP, flavaspidic acid PB, flavaspidic acid AB, and flavaspidic acid BB.

• Microbiology and Biotechnology Letters
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• v.27 no.6
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• pp.491-499
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• 1999

A great variety of the volatile metabolic by-products was formed in yeast cell during alcohol fermentation. The seibel grape (Vitis labrasca) which was grown in the Southern Korea used for wines. The objective of this research was to identify the volatile flavor compounds during alcohol fermentation and aging at 12$^{\circ}C$. saccharomyces cerevisiae and Schizosaccharomyces pombe were inoculated and fermented in seibel grape must. The volatile flavor compounds of logarithmic, stationary and death phases were extracted, concentrated and identified by gas chromatography/mass spectrometer (GC/MS). The volatile flavor compounds were determined by a Hewlett-Packard 5890 II Plus GC which was equipped with Supelcowax 10 fused silica capillary column (60m$\times$0.32mm$\times$0.25${\mu}{\textrm}{m}$ film thickness) wall coated with polyethyleneglycerol. The scan detection method allowed the comparison of the spectrum from the chromatogram of volatile flavor compounds to those in data Wileynbs base library. Among the volatile compounds collected by ether-hexane extraction method, the evolution of 20 main compounds, such as 9 esters (ethyl butyrate, isoamyl acetate, ethyl caproate, n-hexyl acetate, ethl caprylate, ethyl caprate, diethy succinate, ethyl hexadecanoate, 2-pheneethyl acetate), 4 alcohols (3-methyl-1-butanol, 1-hexanol, 1-heptanol, benzoethanol), 4 ketones and acids (2-octanone, caproic acid, caprylic acid, capric acid), 2 furan and phenol (2,6-bis(1,1-dimethyl ethyl)phenol, 2,3-dihydrobenzofuran) were observed during alcohol fermentation and aging. The production of the esters during alcohol fermentation with S. cerevisiae was higher than those of Sch. pombe. The sensory scores of the aged wine samples in aroma, taste and overall acceptability were not significantly different(p<0.05).