• Bulletin of the Korean Chemical Society
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• v.27 no.2
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• pp.286-290
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• 2006

Rapid and facile syntheses of N-alkenyl lactam series via condensation between lactams and a variety of aldehydes such as n-propanal, isobutanal, n-butanal, n-hexanal, n-octanal and phenylacetaldehyde were studied under microwave or conventional heating. Various solid catalysts and solvents were examined to maximize the yields of condensation reactions.

• Korean Journal of Food Science and Technology
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• v.17 no.1
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• pp.51-53
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• 1985

Soy milks prepared from full-fat soy flour, defatted soy flow, soy protein concentrate (SPC) and soy protein isolate (SPI) were fermented with Lactobacillus acidophilus. Effects of lactic fermentation on the flavor and volatile compounds of soy milks were investigated. Sensory evaluation showed that the flavor of soy yogurt beverages was inferior to that of milk yogurt beverage and the flavor of SPI-yogurt beverage was better than that of other soy yogurt beverages. SPI-milk fermented with L. acidophilus was more acceptable than unfermented SPI-milk. Lactic fermentation reduced n-hexanal in SPC-milk and SPI-milk while it increased diacetyl in both soy milks.

• Korean Journal of Food Science and Technology
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• v.18 no.2
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• pp.118-123
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• 1986

Soy milk prepared from soy protein concentrate was fermented with Lactobacillus acidophilus, L. bulgaricus, L. casci, Streptococcus lactis or S. cremoris. Growth and acid production of each organism in soy milk and flavor of soy yogurt beverages were investigated. Volatile compounds in soy milk and soy yogurts were also determined. Among the five organisms tested, L. bulgaricus produced most amount of acid in soy milk while S. cremoris produced least amount of acid in soy mile. Sensory evaluation showed that the flavor of soy yogurt beverages was inferior to that of milk yogurt beverage and the flavor of soy yogurt beverage prepared by L. bulgaricus was better than that of other soy yogurt beverages. Soy milk fermented with L. bulgaricus was more acceptable than unfermented soy milk. Lactic fermentation reduced n-hexanal in soy milk while it produced diacetyl that was not detected in unfermented soy milk.

• 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.

• Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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• 2003.10a
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• pp.139.1-139
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• 2003

검은비늘버섯(Pholiota adipose)의 향기성분을 조사하기 위해 생버섯을 SDE로 추출하여 농축한 후 GC/MS로 정성하였으며 향기특성은 GC/olfactometry를 이용하여 확인하였다. GC/MS로 정성된 화합물은총 52종이었으며 함량이 높은 화합물로는 hexanal (8.55%), n-heptadehyde(13.02%), 2-pentyl furan(4.82%), benzeneacetaldehyde (3.34％), (E,Z) -2,4-Decadienal(3.06％), 6,10-dimethyl 5,9-undecadien-2-one(11.75％) 이었으며 1-octen-3-ol, 3-octanone, 3-octanol, 2-octanol, 1-octanol 등의 C8화합물이 검출되었다. Sniffing test 결과 주요한 향기특성으로는 burnt odor(843, +++), fresh fruity odor(1-hexanol ++), fresh mushroom(n-heptaldehyde, +++), mushroom like(1023, +++), refreshing sweet(benzeneacetaldehyde, +) 등으로 나타났다.

• Food Industry And Nutrition
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• v.7 no.2
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• pp.40-44
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• 2002

매실의 향기성분은 50여종 중 알콜류가 benzyl alcohol, linalool, 1,6-octadien-3-ol, n-haxanol 등 10종, aldehyde류가 2-hexenal, benzaldehyde, n-hexanal 등 3종, acid류가 butandeionic acid, acetic acid, 2종, 2-iodo-hexane 등 hydrocarbon류가 5종, butanedioic acid-diethyl estet를 포함한 ester류가 3종, B-ionone을 포함한 ketone류가 3종 그리고 기타 성분이 2종이었다. 매실이 성숙함에 따라 향기성분의 수가 증가하고 그 함량도 증가하는 경향이었다. 매실의 비휘발성 유기산의 조성은 succinic, fumaric, oxalic, malic, tartaric 및 citric acid이었다. 매실이 비휘발성 유기산은 성숙 초기에는 malic acid와 oxalic acid의 함량이 높았다. Citric acid의 함량이 증가한 반면에 대부분의 유기산은 감소하는 경향이었다. 휘발성 유기산은 성숙중에 formic acid함량은 감소하고 butyric acid의 함량은 증가하는 경향이었다. 총 유기산의 함량은 매실 성숙에 현저히 감소하는 경향이었다.

• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.6
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• pp.738-746
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• 2006

Aroma compounds in four different Byeolmijang made from optional ingredient addition were extracted by SDE (simultaneous steam distillation extraction) and analyzed with GC (gas chromatography) and GC/MS (mass-spectrometry). The major aroma compounds in the four different Byeolmijang during aging were 1-octene-3-ol, hexanal, benzeneacetaldehyde, benzaldehyde, fufural, pyrazine, furan and phenol type compounds. Generally, benzeneacetaldehyde, benzaldehyde, fufural and phenol type compounds were increased during aging. On the other hand, 1-octen-3-ol, hexanal and furan were decreased during aging. Furfural, 2-furanmathanol and benzeneacetaldehyde in Sanghwangjang, 3-methyl-1-butanol, phenol and 1H-indole in Mujang, hexanal, 1-octen-3-ol and 2,4-decadienal in Bizijang and hexanal, tetramethylpyrazine and 2-methoxy-4-vinylphenol in Jigeumjang were identified as major aroma compounds, respectively. Generally, the major aroma compound in four different Byeolmijang with optional ingredient was similar with control and pyrazine, furan and phenol type compounds were decreased to addition with optional ingredient. The major aroma compound in Sanghwangjang with optional ingredient (onion) were 1-hexanol and 2,5-dimethylthiophene and the major aroma compounds were 1,2,4-trithiolane and 2-buthyl-2-octenal in Mujang with optional ingredient (Letinus edodes). Furfural, benzaldehyde, benzeneacetaldehyde, 1,2,4-trithiolane and lenthionine were detected in Bizijang due to the addition of powdered Letinus edodes. Linaool and ${\beta}-lonone$ were detected in Jigeumjang due to the addition of powdered red pepper.

• Korean Journal of Food Science and Technology
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• v.39 no.3
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• pp.246-254
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• 2007

Fresh tea leaves grown in Jeju Island and Jeonnam Province of South Korea were plucked and processed. Volatile compounds (VCs) were analyzed and identified with SPME-GC/GC-MS/GC-O. The VCs of green teas were classified into two major categories based on their aroma characteristics: the Greenish (Group I), and Floral (Group II) odorants. It was found that the VCs were decreased significantly in fresh tea leaves as they were plucked at the later stages of cultivation. The ratio of VCs responsible for Group I and Group II compounds was well-balanced in tea leaves plucked in May, but the balances were changed when the fresh leaves were processed. The major VCs of fresh tea leaves in Jeju and Jeonnam were n-hexanal, E-2-hexenal, Z-3-hexenal, myrcene, benzyl alcohol, linalool, and phenyl alcohol. Also, Jeju and Jeonnam tea leaves had different aroma composition. n-Heptanol, ${\beta}-pinene$, benzaldehyde, and ethyl salicylate were found in Jeju fresh tea leaves, and Z-3-hexenol, E-2-hexenol, and methyl n-heptanoate were detected in Jeju dry tea leaves. On the other hand, Z-linalool oxide and myrcene were found in Jeonnam dry tea leaves. The SPME-GC method showed high reproducibility (RSD, 7.4%) with no-artifact formation. In this study, optimum plucking period of tea leaves could be determined for production of high quality green tea with a well-balanced aroma and characteristic VCs in green tea according to growing areas.

• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.4
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• pp.513-518
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• 2005

Volatile compounds of $\gamma-irradiation$ leeks (Aillum tuberosum R.) were isolated by simultaneous steam distillation and extraction method (SDE) and analyzed by gas chromatography/mass spectrometry (GC/MS) along with the non-irradiated sample. Leeks were irradiated at dose of 20 kGy and non-irradiated samples were considered as control sample. 56 and 54 compounds were identified in non-irradiated and irradiated samples, respectively. These components included the functional groups; alcohols, aldehydes, esters, ketones, N- and S-containing compounds. S-containing compounds such as dimethyl trisulfide, methyl-(Z)-l-proenyl trisulfide, dimethyl disulfide, 3-ethyl-l,2-dithi-5-ene and methyl allyl disulfide were the major compounds. Methyl-(Z)-l-propenyl trisulfide, diallyl trisulfide, (E)-2-hexanal and 3-ethyl-l,2-dithi-5-ene were clearly decreased by the $\gamma-irradiation$, but dimethyl disulfide, diallyl sulfide, allyl methyl sulfide and pyridine were increased by the $\gamma-irradiation$.

• Food Science and Preservation
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• v.6 no.2
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• pp.206-215
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• 1999

Volatile flavor components in five varieties, Bekdo, Chundo, Yumung, Daegubo and Hwangdo, of peach (Prunus persica L.) were extracted by SDE (Simultaneous steam distillation and extraction) method using the mixture of n-pentane and diethylether(1:1, v/v) as an extract solvent. Analysis of the concentrate by capillary gas chromatography and gas chromatography-mass spectrometry led to the identification of 83, 85, 70, 74 and 66 components in Bekdo, Chundo, Yumung, Daegubo and Hwangdo, respectively. Aroma patterns (29 alcohols, 27 ketones, 18 aldehydes, 9 esters, 5 ethers, 3 acids, 6 terpene and derivatives, and 26 miscellaneous) were identified and quantified in five cultivars. Ethyl acetate, hexanal, o-xylene, (E)-2-hexenal, hexanol, (E)-2-hexen-1-ol, benzaldehyde, r-decalactone and r-dodecalactone were the main components in each samples, though there were several differences in composition of volatile components. Beside C$\_$6/ compounds, a series of saturated and unsaturated r- and $\delta$-lactones ranging from chain length C$\_$6/ to C$\_$l2/, with concentration maxima for r-decalactone and r-dodecalactone, were a major class of constituents. Lactones and peroxidation products of unsaturated fatty acid (i.e. C$\_$6/ aldehydes and alcohols) were major constituents of the extract.