• Korean Journal of Food Science and Technology
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• v.29 no.3
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• pp.555-562
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• 1997

The characteristics of mash qualities of takju prepared by using different nuruk (Korean-style bran koji) such as Mucor racemosus nuruk, Rhizopus japonicus nuruk, Aspergillus oryzae nuruk, Aspergillus kawachii nuruk and traditional nuruk were investigated during fermentation. At the begining of fermentation, ethanol content was in the range of $2.0{\sim}3.0%$. However, it increased to $8.2{\sim}12.6%$ after 16 days of fermentation. Takju made from Rhizopus japonicus nuruk showed higher ethanol content than treated otherwise. pH of takju made from Rhizopus japonicus nuruk showed higher value the others. Total acids were $0.15{\sim}0.20%$ at the begining of fermentation, and it increased to $0.086{\sim}1.57%$ after 16 days of fermentation. Total sugar were $16.64{\sim}17.62%$ at the begining of fermentation, but decreased to below 7.00% after 16 days of fermentation. Rhizopus japonicus nuruk showed the lowest level of total sugar content. Except ethanol, iso-amyl alcohol and iso-butyl alcohol were major part of minor alcohol in the mash of takju. Higher concentration of iso-amyl alcohol, iso-butyl alcohol and n-propyl alcohol were found in the mash of Rhizopus japonicus nuruk whereas the level of phenylethyl alcohol was high in the mash of traditional nuruk. Fusel oil was $0.002{\sim}0.411\;mg/mL$ during fermentation.

• Journal of the Korean Society of Tobacco Science
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• v.24 no.2
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• pp.75-81
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• 2002

This study was performed to investigate the influence of curing conditions on the composition of essential oil during curing process of burley tobacco leaves. The curing conditions were the primed curing in vinyl house (house-curing), air-curing barn (air-curing) and stalk-curing in conventional curing house (stalk-curing). Total 90 compounds are identified from the steam volatile oils of harvest and cured tobacco leaves by GC and GC-MS, respectively. The major components were neophytadiene, hexadecanoic acid, 3,8,13-duvatriene-1,5-diols, oxide-9-methylene-3,13-duvadienols, solanone, megastigma-4,6,8-trien-3-ones, phenylacetaldehyde, $\beta$-phenylethyl alcohol, indole, dihydroactinidiolide and phytol. The amount of alcoholic compounds was decreased more than approximately 50% in cured leaves without regard to the curing conditions. $\beta$-Phenylethyl alcohol and 3,8,13-duvatriene-1,5-diols were decreased more in air curing and stalk curing than in house curing. The amounts of phenylacetaldehyde, solanone, $\beta$-damascone, $\beta$ -damascenone, oxysolanone and megastigma-4,6,8-trien-3-ones as ketonic compounds, dihydroactinidiolide and indole as miscellaneous compounds in air-cured and stalk-cured tobacco leaves were 2 times higher than those in house-cured leaves, while esteric and acidic compounds were not changed largely in content by curing conditions.

• Journal of the Korean Society of Food Science and Nutrition
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• v.24 no.2
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• pp.261-267
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• 1995

Low-salted and fermented squid product, squid jeotkal was prepared with the addition of 10% salt and fermented for 50 day at 1$0^{\circ}C$. During fementation of squid, sensory evaluation and changes of volatile components were examined. Volatile flavor components in raw squid and low-salted squid jeotkal were extracted using a rotary evaporating system. The volatile concentrates were identified by GC and GC-MS. Major volatile components of raw squid were methional and 2-methyl-2-propanol. However, alcohols such as propanol, isoamyl alcohol, methionol and phenylethyl alcohol increased during the period of fermentation. The model reaction using microorganism was carried out, in order to confirm formation mechanism ofvolatile flavor compounds of the squid during fermentation. The main volatile components of Pseudomonas sp. D2 model system were isoamyl alcohol and acetoin. Those of Staphylococcus xylosus model system were isoamyl alcohol and phenylacetaldehyde.

• Journal of the Korean Society of Tobacco Science
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• v.25 no.1
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• pp.70-79
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• 2003

$\beta$ -Glucosidase-catalysed synthesis of glucosides with aromatic alcohols and monoterpene alcohols as accepters and cellobiose as a donor in the presence of various commercial $\beta$ -glucosidases were described. $\beta$ -Glucosidases from Aspergillus niger spp,. Trichoderma spp., Penicillium sup. and bitter almond have been shown to catalyze synthesis of $\beta$ -glucosides of benzyl alcohol, 2-hydroxybenzyl alcohol, 4-hydroxybenzyl alcohol, 2-phenylethyl alcohol, geraniol and citronellol in the presence of cellobiose as sugar donor. Among enzyme preparations tested, each $\beta$ -glucosides prepared from Aspergillus niger were isolated in the pure state by Diaion HP-20 and silica gel column chromatography. The products were identified as $\beta$ -glucosyl products of benzyl alcohol, 2-hydroxyhenzyl alcohol, 4-hydroxybenzyl alcohol, 2-phenyl ethyl alcohol, geraniol and citronellol by spectrometry (UV, IR, $^1$H-NMR, $^{13}$ C-NMR) and enzymatic hydrolysis with $\beta$ - glucosidase. Monoterpene alcohols with a sterically hindered hydroxyl group, such as linalool, $\ell$-menthol and $\alpha$-terpineol were not used as acceptors in transglycosylation reaction.

• Korean Journal of Food Science and Technology
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• v.22 no.5
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• pp.549-554
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• 1990

Glycosidically bound fraction was separated from apricot by Amberlite XAD-2 adsorption and eluted with methanol. Aglycones were liberated from the bound fraction by enzymatic hydrolysis, acid hydrolysis or by means of simultaneous distillation-extraction at pH 3.0. A total of 40 components were identified in three bound volatile fractions. Besides linalool oxide, linalool. ${\alpha}-terpineol$, nerol, geraniol, benzyl alcohol and 2-phenylethyl alcohol, previously reported as glycosidically bound volatiles, the following components were identified for the first time as glycosidically bound volatiles in apricot: 2,6-dimethyl-3,7-octadiene-2,6-diol , 3.7-dimethyl-1,5-octadiene-3,7-diol, (E)- and (Z)-2.6-dimethyl-2,7-octadiene-1,6-diol, $3,4-didehydro-{\beta}-ionol,\;3-oxo-{\alpha}-ionol$, $3-hydroxy-7,8-dihydro-{\beta}-ionol,\;3-oxo-7,8-dihydro-{\alpha}-ionol ,\;3-hydroxy-{\beta}-ionone$, eugenol, 4-hydroxyethylphenyl acetate and 2,3-dihydrobenzofuran.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.43 no.3
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• pp.189-193
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• 1998

Volatile components were extracted from leaves of two Boxthorn (Lycium chinense M.) cultivars by using simultaneous distillation and extraction, analyzed by gas chromatography-mass spectrometry. Seventy components were identified : 13 acids, 15 alcohols, 18 hydrocarbons, 13 carbonyls, three esters, three ionones, and five others. The principal volatile components (and their peak area percentage) were n-pentanol (11.2～30.2%), phytol (14.5～28.3%), hexadecanoic acid (13.5～17.1%) 2,3-dihydrobenzofuran (1.5～4.2%), benzyl alcohol (1.9-4.8%), phenylacetaldehyde (1.8～3.2%), and octadecadienoic acid (1.7～10.7%). Fresh leaves showed much higher peak area than that of dried leaf in n-pentanol, n-hexanol, cis-2-penten-l-ol, cis-3-hexen-l-ol, benzyl alcohol, and $\beta$-phenylethyl alcohol, while dried leaves showed much higher content than that of fresh leaves in 9-hydroxytheaspran A, octadecanoic acid and octadecadienic acid.

• Journal of Microbiology and Biotechnology
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• v.22 no.12
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• pp.1749-1757
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• 2012

Makgeolli is a traditional rice wine favored by the general public in Korea. This study investigated the fermentation and sensory characteristics of using wild yeast strains for brewing makgeolli. A non-Saccharomyces cerevisiae strain was isolated from nuruk and termed Y197-13. It showed 98% similarity to Pichia anomala and had an optimal growth temperature of $25^{\circ}C$. Makgeolli was manufactured using koji, jinju nuruk, and improved nuruk as fermentation agents. Y197-13 makgeolli brewed with koji had alcohol and solids contents of 11.1% and 13.9%, respectively. Sweet sensory characteristics were attributed to residual sugars in makgeolli with 6% alcohol. The makgeolli had a fresh sour taste and carbonated taste. Volatile component analysis showed the isoamyl alcohol, phenylethyl alcohol, isoamyl acetate, and fatty acid, including ethyl oleate and ethyl linoleate, relative peak area was higher in Y197-13 makgeolli than in makgeolli with Saccharomyces cerevisiae. These results suggest the wild yeast, Y197-13, as a candidate for brewing makgeolli.

• KSBB Journal
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• v.21 no.6 s.101
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• pp.410-413
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• 2006

The composition of two Bokbunja (Rubus coreanus Miquel) wines (one without mushroom extracts (wine A) and the other is with the extracts (wine B)) has been investigated to improve the quality of Bokbunja wine. The content of solid particle, acidity, crude ash, crude protein of the wine A were 10.5%, 1.36%, 0.45% and 0.05% and those of wine B were 7.4%, 0.54%, 0.31%, and 0.22%, respectively. Crude fat and crude fiber were not detected in both samples. To verify the flavor quality of Bokbunja wine, the volatile components from ethylether extracts of two wines were analyzed using GC/FID and GC/MS. A total number of 12 volatile flavor compounds (6 alcohols, 3 ketones, 1 acid, 1 ester and 1 anhydride) were identified in the two Rubus wines. The major volatile compounds of the wines were 2,3-butanediol, 2,5-furanedione, phenylethyl alcohol, and butanedioic acid and they might affect the major role in the unique flavor of Bokbunja wines.

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.7
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• pp.874-880
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• 2007

Volatile flavor compounds of 4 grape species (Campbell, Sheridan, Red globe, and Meoru) were identified during 3-day storage at either $4^{\circ}C$ or room temperature. Each sample was analyzed by solid-phase micro-extraction (SPME) method combined with gas chromatography-mass spectrometry. Also electronic nose composed of 12 different metal oxide sensors was used to differentiate flavors of grapes. Sensitivities (delta $R_{gas}/R_{air}$) of sensors from electronic nose were obtained by principal component analysis (PCA). Proportion of the first principal component was 99.30% at $4^{\circ}C$ and 99.36% at room temperature, respectively. In our result, flavor patterns of grape can be differentiated according to the storage period. The major volatile flavor compounds were 1-hexanol, hexanoic acid and its ethyl ester, and phenylethyl alcohol with the presence of butanoic acid and its ethyl ester, acetic acid, benzeneacetic acid and its ethyl ester.

• Journal of the Korean Society of Tobacco Science
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• v.14 no.1
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• pp.79-86
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• 1992

Free and glycosidically bound volatiles from three green tobacco leaves(NC 82, KF 109 and Br-21) were separated by nonionic resin Amberlite XAD-2 adsorption column chromatography and election by selective solvents. Aglycones from the glycosidically bound fractions were released by enzymatic hydrolysis with almond B-glucosidase. A total of 20 components identified from free and glycosidically bound fractions, the major components were benzaldehyde, benzyl alcohol, 2-phenylethyl alcohol, 3-oxo- -ionol, 3-hydroxy-B-ionone, 3-oxo-7, 8-dihydro-n-ionol and scopoletin. Six Cl.B norisoprenoids identified in this study, which have been described to possess a characteristic tobacco aroma-enhancing effect, were not presented in free forms but rather bound glycosidic forms.