• Journal of the East Asian Society of Dietary Life
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• v.23 no.4
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• pp.451-460
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• 2013

The purpose of this study is to investigate the volatile compounds of Korean traditional gochujang from various districts. The volatiles from each traditional gochujang are being extracted by simultaneous steam distillation extraction (SDE), and analyzed by gas chromatography (GC) and gas chromatography/mass spectrometry (GC/MS). Twenty compounds are identified as major volatile components which include 8 esters, 4 alcohols and 4 acids. The most traditional gochujang possesses more volatile components rather than commercial gochujang products. Most acids come from fatty acids and the alcohols derive from the oxidative degradation of linolenic acid. The most abundant volatile compounds for both traditional and commercial gochujang include 10 compounds such as 2-methyl-1-propanol, hexanal, 2-methyl-1-butanol, octanoic acid ethyl ester, as well as the various type of acids and esters. They represent most of the total GC peak areas, respectively. From the results, the characteristics of the flavors for traditional gochujang from each district are not clear but have shown various components than the commercial products.

• Analytical Science and Technology
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• v.34 no.1
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• pp.23-35
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• 2021

In order to measure the volatile organic compounds (VOCs) of a sample which is too large to use commercially available chamber, a stainless steel vacuum chamber (VC) (with an internal diameter of 205 mm and a height of 50 mm) was manufactured and the temperature of the chamber was controlled using an oven. After concentrating the volatiles of the sample in the chamber by helium gas, it was made possible to remove residual volatile substances present in the chamber under reduced pressure ((2 ± 1) × 10-2 mmHg). The chamber was connected to a purge & trap (P&T) using a 6 port valve to concentrate the VOCs, which were analyzed by gas chromatography-mass spectrometry (GC-MS) after thermal desorption (VC-P&T-GC-MS). Using toluene, the toluene recovery rate of this device was 85 ± 2 %, reproducibility was 5 ± 2 %, and the detection limit was 0.01 ng L-1. The method of removing VOCs remaining in the chamber with helium and the method of removing those with reduced pressure was compared using Korean drinking water regulation (KDWR) VOC Mix A (5 μL of 100 ㎍ mL-1) and butylated hydroxytoluene (BHT, 2 μL of 500 ㎍ mL-1). In case of using helium, which requires a large amount of gas and time, reduced pressure ((2 ± 1) × 10-2 mmHg) only during the GC-MS running time, could remove VOCs and BHT to less than 0.1 % of the original injection concentration. As a result of analyzing volatile substances using VC-P&T-GC-MS of six types of cell phone case, BHT was detected in four types and quantitatively analyzed. Maintaining the chamber at reduced pressure during the GC-MS analysis time eliminated memory effect and did not affect the next sample analysis. The volatile substances in a cell phone case were also analyzed by dynamic headspace (HT3) and GC-MS, and the results of the analysis were compared with those of VC-P&T-GC-MS. Considering the chamber volume and sample weight, the VC-P&T configuration was able to collect volatile substances more efficiently than the HT3. The VC-P&T-GC-MS system is believed to be useful for VOCs measurement of inhomogeneous large sample or devices used inside clean rooms.

• Analytical Science and Technology
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• v.30 no.4
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• pp.174-181
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• 2017

Bio-liquid is a liquid by-product of the hydrothermal carbonization (HTC) reaction, converting wet biomass into solid hydrochar, bio-liquid, and bio-gas. Since bio-liquid contains various compounds, it requires efficient sampling method to extract the target compounds from bio-liquid. In this research, fatty acid methyl ester (FAME) in bio-liquid was extracted based on hollow fiber supported liquid phase microextraction (HF-LPME) and determined by Gas Chromatography-Flame Ionization Detector (GC-FID) and Gas Chromatography/Mass Spectrometry (GC/MS). The well-known major components of biodiesel, including methyl myristate, palmitate, methyl palmitoleate, methyl stearate, methyl oleate, and methyl linoleate had been selected as standard materials for FAME analysis using HF-LPME. Physicochemical properties of bio-liquid was measured that the acidity was 3.30 (${\pm}0.01$) and the moisture content was 100.84 (${\pm}3.02$)%. The optimization of HF-LPME method had been investigated by varying the experimental parameters such as extraction solvent, extraction time, stirring speed, and the length of HF at the fixed concentration of NaCl salt. As a result, optimal conditions of HF-LPME for FAMEs were; n-octanol for extraction solvent, 30 min for extraction time, 1200 rpm for stirring speed, 20 mm for the HF length, and 0.5 w/v% for the concentration of NaCl. Validation of HF-LPME was performed with limit of detection (LOD), limit of quantitation (LOQ), dynamic range, reproducibility, and recovery. The results obtained from this study indicated that HF-LPME was suitable for the preconcentration method and the quantitative analysis to characterize FAMEs in bio-liquid generated from food waste via HTC reaction.

• Korean journal of food and cookery science
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• v.17 no.1
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• pp.55-59
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• 2001

To investigate the usefulness of Allium senescens as a aromatic edible plant, volatile flavor components and flavor pattern were analyzed. Essential oils of fresh and freeze dried Allium senescens were extracted by SDE(simultaneous steam distillation and extraction) method using diethyl ether as solvent. And their volatile flavor components were analyzed by gas chromatography(GC) and gas chromatography-mass spectrometry (GC-MS). A total of 46 components, including 11 hydrocarbons, 9 aldehydes, 4 alcohols, 2 esters, 7 acids, 4 ketones and 9 sulfur containing compounds were identified in fresh Allium senescens. In freeze dried Allium senescens, 8 hydrocarbons, 5 aldehydes, 3 alcohols, 5 esters, 2 acids, 3 ketones and 4 sulfur containing compounds were identified. Volatile flavor patterns of Chinese chive and Allium senescens were compared using electronic nose. The score of first principal component was significantly different in Allium senescens and Chinese chive.

• Preventive Nutrition and Food Science
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• v.17 no.4
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• pp.310-314
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• 2012

Thirty-two different volatile oils were identified from Allomyrina dichotoma (A. dichotoma) larvae by gas chromatography/mass spectrometry (GC/MS). The major volatile components were 2,2,4-trimethyl-3-carboxyisopropyl pentanoic acid isobutyl ester (5.83%), phenol,2,6-bis(a,a-dimethyl ethyl)-4-(1-methyl-1-phenylethyl) (5.72%), heptacosane (5.49%) and phenol,2,4-bis(1-methyl-1-phenylethyl) (5.47%). The composition of the fatty acids in A. dichotoma larvae was also determined by gas chromatography (GC) and fourteen constituents were identified. Oleic acid (19.13%) was the most abundant fatty acid followed by palmitic acid (12.52%), palmitoleic acid (3.71%) and linoleic acid (2.08%) in 100 g of A. dichotoma larvae on a dry weight basis. The quantity of unsaturated fatty acids (64.00%) were higher than that of saturated ones (36.00%). The predominant fatty acids in A. dichotoma consist of monounsaturated fatty acid (MUFA, 57.70%) such as oleic acid, myristoleic acid and palmitoleic acid, followed by saturated fatty acids (36.00%) and polyunsaturated fatty acids (PUFA, 6.50%). In particular, the presence of essential fatty acids, such as linoleic (5.30%) and linolenic acid (0.40%) give A. dichotoma larvae considerable nutritional and functional value and it may be a useful source for food and/or industrial utilization.

• Korean Journal of Food Science and Technology
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• v.26 no.1
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• pp.68-73
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• 1994

An attempt was made to derermine the volatile flavor components of Dioscorea japonica. Essential oils from roots of the samples were isolated by simultaneous steam distillation-extraction(SDE) method using diethyl ether as solvent. Concentrated samples were analyzed by gas chromatography(GC) and combined gas chromatography-mass spectrometry(GC-MS). Fifty nine volatile flavor components, including 35 hydrocarbons, 5 aldehydes, 1 ketone, 9 alcohols, 2 esters, 3 acids and 4 miscellaneous ones were confirmed in the young roots of Dioscorea japonica. Forty two components, including 23 hydrocarbons, 2 aldehydes, 7 alcohols, 1 ester and 8 acids and 1 miscellaneous one were confirmed in the roots of mature stage. ${\sigma}-3-Carene$ and dodecanoic acid were regarded as the most abundant components in young and mature roots repectively. The profile of volatile flavor components was markedly different in young and mature roots of Dioscorea japonica.

• Korean Journal of Food Science and Technology
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• v.28 no.5
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• pp.822-826
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• 1996

Volatile flavor components from various edible portions of Capsella bursa-pastoris were collected by simultaneous steam distillation-extraction (SDE) method using diethyl ether as solvent. Essential oils were analyzed by gas chromatography (GC) and combined gas chromatography-mass spectrometry (GC-MS). Thirty four volatile flavor components, including 12 hydrocarbons, 2 aldehydes, 2 ketones, 5 alcohols, 1 ester, 10 acids and 2 miscellaneous ones were confirmed in whole samples. Thirty one components, including 11 hydrocarbons, 5 aldehydes, 4 ketones, 5 alcohols, 1 esters and 5 miscellaneous ones were confirmed in leaves. Twenty four components, including 5 hydrocarbons, 1 aldehyde, 2 ketones, 6 alcohols, 2 esters, 1 acid and 7 miscellaneous ones were confirmed in roots. The kinds and amounts of volatile flavor components revealed different patterns depending upon various edible portions. Relatively greater numbers of volatile flavor components were identified in leaves compared with roots of these wild plants. The characteristic aroma of Capsella bursa-pastoris appeared to be due to combination of C6 alcohol and acids, terpene alcohol and sulfur containing compounds.

• Korean Journal of Food Science and Technology
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• v.25 no.5
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• pp.426-429
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• 1993

This study was conducted to determine the effects of stamping and roasting treatment on change of volatile flavor components in curry powder aged for 6th month at $37^{\circ}C$. Volatile flavor components were collected by simultaneous distillation extraction method. Essential oils were analyzed by gas chromatography(GC) and combined gas chromatography-mass spectrometry(GC-MS). Aged curry powder contained large amounts of terpene hydrocarbones, terpene alchols and aromatic ether compounds. By stamping and roasting treatment, the peak area generally increased until 15min. at $70^{\circ}C$, whereas, that of peak decreased after 20 min. at $80^{\circ}C$, respectably.

• Korean journal of food and cookery science
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• v.22 no.6 s.96
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• pp.768-773
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• 2006

The aroma components of german chamomile tea in Europe and kukwha (Chrysanthemum boreale Makino) tea in Korea belonging to genus chrysanthemum were analyzed and compared. The volatile components of chamomile tea and kukwha tea were collected by a simultaneous steam distillation-solvent extraction method (SDE). The extracted components were analyzed gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS). Forty-six compounds, including cubebene(14.59%), ${\beta}$-elememe(4.88%) and ${\delta}$-cadinol(1.54%) were identified in chamomile tea. Forty-five compounds including santalol(6.25%), bomyl acetate(3.47%), farnesene(3.37%), 1,8-nonadiene (2.80%), caryophyllene oxide(2.77%) and thymol (2.16%) were identified in kukwha tea. Twenty-two compounds including 4-terpineol, ${\alpha}$-terpineol, thymol, phenylacetaldehyde, V-terpinene were found in both samples.

• Korean Journal of Food Science and Technology
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• v.26 no.4
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• pp.359-364
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• 1994

Volatile flavor components from various edible portions of Calystegia japonica $(T_{HUNB})\;C_{HOIS}$ were collected by simultaneous steam distillation-extraction(SDE) method using diethyl ether as solvent. Essential oils were analyzed by gas chromatography(GC) and combined gas chromatography-mass spectrometry(GC-MS). Thirty nine volatile flavor components, including 21 hydrocarbons, 1 aldehyde, 4 ketones, 7 alcohols, 4 esters, 1 acid and 1 miscellaneous one were confirmed in leaves. Twenty six components, including 16 hydrocarbons, 2 aldehydes, 3 ketones and 5 alcohols were confirmed in stems, and 52 components, including 26 hydrocarbons, 2 aldehydes, 5 ketones, 13 alcohols, 1 ester, 1 acid and 4 miscellaneous ones were confirmed in roots. The kinds and amounts of volatile flavor components revealed different patterns depending upon various edible portions. Relatively greater numbers of volatile flavor components were identified in roots compared with other portions of this wild plant.