• 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 Applied Biological Chemistry
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• v.50 no.1
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• pp.29-31
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• 2007

• Applied Biological Chemistry
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• v.39 no.4
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• pp.249-254
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• 1996

The volatile flavor components in mash of nonglutinous rice Takju brewed with or without addition of the starter were determined by GC and GC-MS using polar column. Various kinds of volatile components including alcohols(10), esters(9), organic acids(2) and aldehydes(7) were found in mash of nonglutinous rice Takjus. At the beginning stage of fermentation, 3 to 7 volatile flavor components were detected. The number of volatile flavor components were increased to 26 of to 28 after 16 days fermentation. Early in the brewing, just 3 kinds of flavor components including ethyl acetate, ${\beta}-phenylethyl$ acetate and acetic acid were detected in mash of nonglutinous rice Takju without the addition of the starter, when starter is added additional compounds of alcohol including ethanol were detected, which is suggested to be the effect of flavors originated from the starter. The common flavor compounds through the entire process of fermentation in mash of nonglutinous rice Takju were ethyl acetate, ${\beta}-phenylethyl$ acetate and acetic acid. The relative amount(peak area %) of flavor components were changed with the fermentation period, but the major volatile flavor components were ethyl alcohol, iso-amyl alcohol, hexenyl alcohol, ethyl acetate, ${\beta}-phenylethyl$ acetate and ${\beta}-phenylethyl$ alcohol. The relative amount(peak area %) of ethyl alcohol was the highest in mash of nonglutinous rice Takju with addition of starter. When the starter was not added in the mash of nonglutinous rice Takju, any alcoholic components were not detected in the early stage of fermentation. But the percent of peak area hexenyl alcohol was the highest after 16 days fermentation. Especially few sorts of ester were detected in mash of nonglutious rice Takju without addition of starter by 3 days fermentation.

• Food Science and Biotechnology
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• v.16 no.1
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• pp.159-162
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• 2007

Optimization of the fermentation medium for phenylethyl alcohol (PEA) production by Pichia anomala SKM-T was performed. The carbon source (glucose), nitrogen source (L-phenylalanine), and initial pH value were independent variables of the optimized medium. The central composite rotatable design was used for the experimental design and the analysis of the results. The optimum medium composition for the maximal production (621.27 mg/L) of PEA was found to be an initial pH of 5.03, and concentrations of L-phenylalanine at 6.53 and glucose at 6.11 g/L (w/v). This experimental finding is in close agreement with the model prediction (702.79 mg/L; desirability 0.884) with an 11.6% difference.

• 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.

• Korean Journal of Food Science and Technology
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• v.27 no.2
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• pp.235-240
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• 1995

Volatile components and fusel oils of sojues and mashes brewed by four different traditional methods such as Andong soju, Moonbaeju, Leekangju, Jindo-hongju were studied. Fusel oil contents of mashes were in the range of $0.09{\sim}0.32{\;}mg/ml$, but those of sojues were increased to reach the range of $0.35{\sim}0.87{\;}mg/ml$. Fusel oil contents of Moonbaeju and Andong soju were lower than those of other sojues. Among fusel oils, iso-amyl alcohol content was highest in all sojues and mashes. Thirty-three volatile components were detected in mashes and distillates which were fermented for 16 days. Among them, seven alcohols, seven esters, four aldehydes and one acid were identified. Furfural that was not found in mashes were detected in four type of sojues. Mashes had more various volatile components than sojues had. Higher content of n-hexyl alcohol, acetic acid and phenethyl alcohol were found in mashes while more iso-amyl alcohol were found in sojues.

• Journal of Life Science
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• v.19 no.9
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• pp.1333-1336
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• 2009

The purpose of this study was to characterize the aromas of rose tea and rosehip tea. Aroma compounds were extracted by simultaneous distillation and extraction method using a Likens and Nickerson's extraction apparatus. The concentrated aroma extracts were analyzed and identified by GC and GC-MS. Thirty-eight compounds, including phenylethyl alcohol, citronellol, menthol, menthone, linalool and geraniol, were isolated and identified in rose tea. Thirty-six compounds, including menthol, $\alpha$-anethole, $\alpha$-terpinolene, menthone, linalool and 6-methyl-5-heptene-2-one, were isolated and identified in rosehip tea. Large amounts of phenyl ethyl alcohol and citronellol were found in rose tea, while large amounts of menthol and $\alpha$-anethole were found in rosehip tea.

• Journal of Microbiology and Biotechnology
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• v.13 no.5
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• pp.800-808
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• 2003

Three strains of yeasts, Pichia farinosa SKM-1, Pichia anomala SKM-T, and Galactomyces geotrichum SJM-59, produced volatile flavor compounds during fermentation. To investigate these volatile flavor compounds, the liquid culture broth of the three yeast strains were extracted with methylene chloride, and then GC and GC-MS analyses were conducted. Flavor analyses revealed that 5, 12, and 15 kinds of volatile compounds were isolated, and 4, 8, and 11 volatile flavor compounds were identified, respectively. Phenylethyl alcohol was identified with the common volatile flavor compound of Pichia farinosa SKM-1, Pichia anomala SKM-T, and Galactomyces geotrichum SJM-59. 1H-indole-3-ethanol, a precursor of plant growth hormone, was identified from Pichia anomala SKM-T.

• Korean Journal of Food Science and Technology
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• v.22 no.5
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• pp.543-548
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• 1990

Volatile components of fresh apricot (Prunus armeniaca var. ansu Max.) were isolated by simultaneous distillation-extraction at two different pH values of 3.1 and 7.0 and by headspace trapping method. The volatiles were analyzed by GC and GC-MS. A total of 80 components were identified in the three aroma concentrates, including 9 naphthalene derivatives that were not previously reported in apricot. Of components identified in native pH (3.1) sample, the major components were aliphatic $C_6$ aldehydes and alcohols, monoterpene alcohols, benzyl alcohol, ${\beta}-phenylethyl$ alcohol and naphthalene derivatives, while those in neutral pH(7.0) sample and headspace volatiles were aliphatic $C_6$ aldehydes and alcohols. Simultaneous distillation-extraction at pH 3.1 was significantly increased the concentration of n-hexanal, trans-2-hexenal, cis-3-hexen-1-ol, linalool oxide, linalool, ${\alpha}-terpineol$, nerol, geraniol, benzyl alcohol, ${\beta}-phenylethyl$ alcohol and naphthalene derivatives. These results demonstrate that above the components are present in glycosidically bound forms in apricot.

• Korean Journal of Agricultural Science
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• v.38 no.2
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• pp.205-212
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• 2011

The potential factors for quality loss of cleaned fresh ginseng and technology to be associated with the improvement of marketability through pre-packaging fumigation were examined. Major microorganisms isolated from fresh ginseng included Botrytis cinerea, and Erwinia sp. Others such as Cylindrocarpon sp., Fusarium spp., Pennicilium spp., Bacillus spp. were also found at relatively low frequency. The bacterial density of vacuum packaged fresh ginseng rapidly increased during simulated marketing. Little correlation between bacterial growth and package swelling was found. In order to improve packaging method of fresh ginseng, pre-packaging treatment of 2-phenylethyl alcohol (PE, 100 uL/L, 4 hr) was examined. The fumigation treatment effectively inhibited the growth of bacteria density and also effective on keeping firmness of ginseng root, especially in cortical portion. The internal gas compositions of plastic container packaged for ginseng were approximately ranged between 6 to 8% $O_2$and 3 to 4% $CO_2$. The $O_2$ level of fumigation treatment was lower than control whereas $CO_2$ level was higher. The upsurge of ethylene evolution I day after simulated marketing was found only in fumigation treatment but it returned to ordinary level at day 2. The sucrose content of 2-PE treatment was significantly reduced at 5 days after simulated marketing but reducing sugars like glucose and fructose remained at higher level. The difference in sugar levels was reduced after 10 days of simulated marketing. The decay of fresh ginseng began at the lateral or fine root, which is weak to physical damage, in general. The epidermis was more damaged. Plastic container packaging with PE fumigation could be an alternative to vacuum packaging, which allows an aerobic environment and prevents anaerobic respiration. Further study of pre-package fumigation is required to improve technology of fresh ginseng marketing.