• Bulletin of the Korean Chemical Society
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• v.34 no.6
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• pp.1703-1707
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• 2013

A fast and simple sampling and sample preparation device, (NTD) has been developed and applied to sample and analyze volatile components from ground coffee beans. Coffee fragrances and other volatile organic compounds (VOCs) were sampled by the NTD and then analyzed by gas chromatograph-mass spectrometry (GC/MS). Divinylbenzene (DVB) particles (80/100 mesh size) were the sorbent bed of the NTD. More than 150 volatile components were first identified based on the database of the mass library and then finally 30 fragrances including caffeine were further confirmed by comparing experimental retention indices (i.e. Kovat index) with literature retention indices. Total sampling time was 10 minutes and no extra solvent extraction and/or reconstitution step need. Straight n-alkanes (C6-C20) were used as retention index probes for the calculation of experimental retention indices. In addition, this report suggests that an empty needle can be an alternative platform for analyzing polymers by pyrolysis-GC/MS.

• Journal of Microbiology and Biotechnology
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• v.5 no.3
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• pp.143-148
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• 1995

A strain producing soybean paste flavor was isolated from traditional Korean soybean paste. The isolate was identified as Bacillus subtilis PM3. The neutral fraction representing the traditional soybean paste aroma was obtained from the whole volatile components produced by B. subtilis PM3 in cooked soybean. Each separated peak from the neutral fraction of gas chromatogram was identified by gas chromatography-mass spectrometry (GC/MS) and Kovat's retention index, and the aromas of each peak were investigated by a sniffing test with the exercise panel. The twenty-nine components, including six character impact compounds and twelve components of flavors of Korean soybean paste, were confirmed. Some regions of gas chromatogram represented the soybean paste odor. It has been confirmed that traditional Korean soybean paste can be manufactured with the strain B. subtilis PM3.

• Journal of Microbiology and Biotechnology
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• v.3 no.4
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• pp.270-276
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• 1993

We characterized the character impact compounds of flavors of the fermented Korean soy sauce manufactured with both the traditional and the improved Meju made with different strains. The whole flavor samples were obtained by extracting each volatile flavor phase from both the traditional and the improved soy sauce. To get more detailed information, each whole volatile flavor was further fractionated into the basic, acidic, phenolic and neutral fractions. Each separated peak from the whole and fractionated flavor samples on gas chromatogram was identified by GC/MS and Kovat s retention index, and likewise the aroma of each peak was investigated by a sniffing test with the exercised panel. We were able to identify 15 groups of ingredients with the characteristic soy sauce aroma from the soy sauce made with the traditional Meju and 6 groups from the soy sauce manufactured with the improved Meju made with Aspergillus oryzae. The character impact compounds the two soy sauces were different from each other.

• Applied Biological Chemistry
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• v.40 no.6
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• pp.514-518
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• 1997

In order to investigate the possible use of spices as natural preservatives) antimicrobial activities of garlic and ginger, representative spices, were examinated. Distilled components of garlic and ginger were also analyzed. Each extract of garlic was more suppressive on the growth of Gram negative bacteria than that of Gram positive bacteria. Extracts of garlic were showed effective suppressions on the growth of yeasts. Of the extracts of garlic, ether extract was highest among antimicrobial activities. In the case of ginger, ether extract of ginger was effective for growth inhibition of tested bacteria. Distilled components of garlic and ginger were extracted by simultaneous steam distillation extraction apparatus. The concentrates were analyzed with GC/MSD and Kovat's retention index and identified 13 components and 21 components respectively. Distilled components of garlic and ginger were full of sulfur compounds and hydrocarbons, respectively. di-2-Propenyl disulfide, methyl 2-propenyl disulfide, 2-vinyl-4H-1,3-dithiirane and 3,3'-thiobis-1-propene were major principal aroma compounds in garlic. ${\alpha}-zingibirene$, ${\beta}-phellandrene$, ${\beta}-sesquiphellandrene$ and camphene were major principal compounds in ginger.

• Journal of Microbiology and Biotechnology
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• v.6 no.4
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• pp.278-285
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• 1996

We identified volatile components of traditional Korean soy sauce and soybean paste which had been manufactured with the same traditional Meju with a view to improving the quality of traditional Korean soy sauce and soybean paste. All of the volatile components were extracted by simultaneous steam distillation-extraction (SDE) apparatus. To obtain more detailed information, whole volatile components were separated into fractions. The volatile components of the whole and of each fraction were identified by GC-mass and Kovat's retention index. Sixty two and eighty six components were identified in traditional Korean soy sauce and soybean paste, respectively. Many aroma components of traditional Korean soy sauce differ from those of traditional Korean soybean paste. It was confirmed that many aroma components of traditional Korean soy sauce and soybean paste are completely different from those of Japanese fermented soy sauce (Shoyu) and soybean paste (Miso).

• Journal of the Korean Society of Food Science and Nutrition
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• v.31 no.1
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• pp.26-31
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• 2002

Volatile compounds from three parts of needles, sprouts and twigs in Pinus densiflora were extracted by solid phase microextraction (SPME) and dynamic headspace analysis (DHA). separated by gas chromatography, and identified by using mass selective detecter and Kovat's retention index. The amounts of monoterpenes isolated by SPME and DHA were 66.7% and 14.3% in needles, 90.6% and 0.7% in sprouts, and 90.6% and 1.2% in twings, respectively. The amounts of sesquiterpenes detected only by SPME were 25.8% in needles, 4.4% in twings and 1.5% in sprouts. And the amounts of oxygenated terpenes isolated by SPME and DHA were 4.7% and 79.0% in sprouts, 3.7% and 70.4% in twigs, and 1.0% and 50.7% in needles, respectively. The kinds of volatile compounds isolated by SPME were similar to those by solvent extraction, but the number of compounds identified to hate a boiling point below 5$0^{\circ}C$ by UHA was larger than that of SPME.

• Korean Journal of Food Science and Technology
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• v.30 no.2
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• pp.260-265
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• 1998

In this study, volatile flavor compounds in sesame oils were analyzed by using pure-and-trap method and a gas chromatography. 2-ethoxy-3-ethylpyrazine was used as an internal standard and retention index (Kovat's number) for the volatiles were determined through the use of a n-paraffin $(C_5-C_{25})$ standards. A total of 33 volatile compounds including 14 pyrazines, 7 thiazoles, 4 pyridines, 2 oxazoles and 6 others were identified in the sesame oils. By comparing the total yields of volatile flavor compounds, the pyrazines are the most abundant compounds all of the oil samples and considered as good contributor to characteristic flavor of sesame oil. The oil from the seeds roasted in the electric pan at $200^{\circ}C$ and $230^{\circ}C$ for 10 minutes generated 277.06 ppm, 264.81 ppm in pyrazine and 15.16 ppm, 13.19 ppm in thiazole, respectively. The sensory evaluation of oil samples was also investigated. The sesame oil obtained from the sesame seeds roasted at $200^{\circ}C$ for 10 minutes with electric pan showed good flavor scores and quality among the all of samples.

• Journal of the Korean Society of Food Science and Nutrition
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• v.30 no.6
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• pp.1033-1037
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• 2001

Garlic oleoresins were made by extracting with four solvents of methanol, methyl acetate hexane and acetone from chopped garlic, respectively, and the volatile compounds of each extract were separated by gas chromatography installed with polar (supelcowax-10$^{TM}$) and nonpolar (HP-5) capillary columns, respectively, and identified by matching mass data of mass selective detector and Kovat\`s retention index with references. The numbers of the volatile compounds identified the garlic oleoresin by polar and nonpolar columns from in garlic oleoresins were 41 and 32, respectively. In polar column, 13 pyrans, 11 sulfur-containing compounds 6 furans 2 alcohols and 2 heterocyclic compounds were identified. In nonpolar column, 11 sulfur-containing compounds 5 acids 3 furans and eugenol were identified. The major sulfur-containing compounds identified from the oleoresins were 3, 3'-thiobis-1-propene, methyl 2-propenyl disulfide, dimethyl trisulfide, di-2-prnpenyl-trisulfide, 2-thiophenecarboxylic acid. The amount of these sulfur-containing compounds isolated from the oleresins were more abundant in polar column than in nonpolar column. The most efficient solvent for extracting volatile compounds of garlic was methanol but the most useful solvent for extracting sulfur-containing compounds was methyl acetate of less polarity.y.