• Applied Biological Chemistry
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• v.46 no.3
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• pp.207-213
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• 2003

Kochujang was prepared for this study with raw material inoculated by commercial enzyme of amylase and protease. Volati1e compounds of Kochujang were analyzed using a purge and trap method during fermentation and identified with GC-MSD. Total 54 kinds of volatile flavor components like 16 kinds of alcohol, 16 kinds of ester, 7 kinds of acid, 4 kinds of aldehyde, 2 kinds of alkane, 1 kind of benzene, 3 kinds of ketone, 1 kind of alkene, 2 kind of amine, 1 kind of phenol, other 1 were found. Total number of volatile flavor detected right after manufacturing were 23 kinds like 3 kinds of alcohol, 6 kinds of ester, 3 kinds of aldehyde. After 30 days storage, total number of volatile flavor went up to 31 kinds with addition of 4 kinds of alcohol, 1 kind of ester. The total number of volatile flavor after 120 days storage were increased to 49 kinds. Volatile flavor compounds detected during the storage period were total 20 kinds like 6 kinds of alcohol such as 2-methyl-1-propanol, ethanol, 3-methyl-1-butanol, 5 kinds of ester such as ethyl acetate, isoamyl acetate, ethyl butyrate, 3 kinds of aldehyde such as butanal, acetaldehyde and 6 kinds of others. Even though peak area % of flavor compound varied depends on fermentation period, ethanol, ethyl acetate, ethyl butyrate, ethenone, 2-methyl-1-propanol, 3-methyl-1-butanol were the main compounds that consisted of flavor from Kochujang which was made with enzyme treatment. Ethly acetate showed the highest result in the treatment of right after manufacturing, 3-methyl-1-butanol had up to 90th day and ether were the other days.

• Analytical Science and Technology
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• v.22 no.1
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• pp.44-50
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• 2009

In this study, the use of purge & trap GC-MS technique for determination of methylmercury in sediment samples was described. The method detection limit of the method was determined as 0.06 ng/g and the recovery of the method was $102{\pm}11.4%$, with precisions better than 11.2%. The method was validated by analysis of CRMs such as ERM CC580 (estuarine sediment) and IAEA 405 (sediment). Additionally, the performance of the method was tested on river sediment samples and the analytical results were compared with those of the GC-CVAFS, which has been widely used for methylmercury analysis.

• Microbiology and Biotechnology Letters
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• v.27 no.3
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• pp.236-245
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• 1999

Andong Soju is a Korean traditional distilled liquor brewed with Nuruk which is cultured with wild microorganisms. To provide useful information for scientific production and systematic quality control of traditional distilled liquor, the effects of mixed culture of the alcoholic yeasts and saccharifying molds isolated from the Nuruk, and mashes on the flavor and sensory characteristics were investigated. Distillate from mashes cocultured with Saccharomyces cerevisiae and Hansenula anomala using Mucor Nuruk was compared with distillate from mashes brewed with Andong Nuruk and with distillate from plant fermented mashes to analyze their flavor characteristics. The volatile flavor compounds in distillates were analyzed by GC and GC-MS using direct injection, solvent extraction, and purge & trap methods. Alcohols such as 3-methyl-1-butanol, 2-methyl-1-propanol, 1-propanol, and 2-phenyl ethanol; aldehydes such as acetaldehyde and 2-furancar-boxaldehyde; esters such as ethyl ester of acetic acid, hexanoic acid, octanoic acid, decanoic acid; alkanes, alkenes, ketone, sulfur, and pyrone compounds were detected. Alcohols were chief components of flavor compounds. No significant difference in overall acceptability test was shown among three experimental groups(p<0.05), but Nuruk-like aroma, Kaoliangchiew-like aroma, sweet taste, and well rounded mouthfeel showed significant differences among them(p<0.05).

• Fisheries and Aquatic Sciences
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• v.4 no.4
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• pp.229-237
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• 2001

In order to identify of volatile flavor compounds and polycyclic aromatic hydrocarbons (PAHs) in commercial liquid smokes, this study was conducted to analyze volatile flavor compounds by solvent extraction and/or Purge & Trap method/GC/MSD. A total of 156 volatile flavor compounds were detected in 6 commercial liquid smokes, and these compounds were composed mainly of 12 aldehydes, 60 ketones, 7 alcohols, 14 acids, 20 esters, 24 aromatic compounds, 7 furans and 12 miscellaneous compounds. Ketones $(806.6-7,573.9\mu g/mL)$ and aromatic compounds $(282.6-7,896.3 \mu g/mL)$ were more abundant than others. The PAHs known as carcinogen have not been detected in this study. The acids $(422.9-4,903.1\mu g/mL)$ was identified in relatively high concentration compared to other groups. Phenol and its derivatives among aromatic compounds were in relatively high concentration. Especially, the phenol and its derivatives including o-cresol, guaiacol, 4-ethylguaiacol and syringol were in higher concentration.

• Preventive Nutrition and Food Science
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• v.19 no.4
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• pp.314-320
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• 2014

Flavor quality of Liriopis tuber tea that was made using a steaming process was studied by measuring changes in headspace volatile compounds. Headspace volatile compounds of the prepared samples were isolated, separated and identified by the combined system of purge & trap, automatic thermal desorber, gas chromatography, and mass selective detector. As steaming frequencies were increased, the area percent of aldehydes decreased from 32.01% to 3.39% at 1 and 9 steaming frequency times, respectively. However, furans and ketones increased from 18.67% to 33.86% and from 9.60% to 17.40% at 1 and 9 times, respectively. The savory flavor of Liriopis tuber tea was due to a decrease in aldehydes contributing a fresh flavor at the 1st steaming process and newly generated furans from nonenzymatic browning with repeated steaming frequencies. These results will provide basic information for quality control of the newly developed Liriopis tuber tea.

• Journal of Life Science
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• v.9 no.5
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• pp.575-580
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• 1999

Even if odorous compounds remained very low concentration in water, it caused strong odor. Because Geosmin and most of odorous compound had very vaporization, those were difficult to analyze with GC/MSD and Purge & Trap. So, we needed pre-treatment method for decreasing amounts of extracting solvents, improving recovery efficiencies and increasing analytical efficiencies. This study developed efficient technology for analyzing odorous compounds, using various adsorbents and extracting solvents. The optimum adsorbent was XAD resins. Especially, XAD-2, XAD-7 and XAD-2010 were superior, but XAD-2 of these and MTBE was the optimum extraction solvent. Other extraction solvent's efficiency was in order of MTBE>Dichloromethane>n-Hexane>Diethylether. The optimum NaCl dosage for increasing efficiency was 5g in liquid-liquid extraction method. The shaking time(0∼24hr) had no concern with adsorption efficiency. The optimum adsorbent was XAD-2 resin and extraction solvent was MTBE. Dosing NaCl, adsorption efficiency was increased in liquid-liquid extraction method, but NaCl has no effect on liquid-solid extraction method. In this experimental results, this method will apply to not only Geosmin but other well-known odorous compounds (2-MIB, IBMP, IPMP, TCA) and algae toxins (Mycrocystin, Anatoxin etc)

• Journal of Environmental Health Sciences
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• v.25 no.3
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• pp.103-107
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• 1999

Even if odorous compounds remain very low concentration in water, it cause strong odor. Because Geosmin and most of odorous compound had very low vaporization, those were difficult to analyze with GC/MSD and Purge & Trap. So, we needed pre-treatment method for decreasing amounts of extracting solvents, improving recovery efficiencies and increasing analytical efficiencies. This study developed efficient technology for analyzing odorous compounds, using various adsorbents and extracting solvents. The optimum adsorbent was XAD resins. Especially, XAD-2, XAD-7 and XAD-2010 were superior, but XAD-2 of these and the optimum extraction solvent is MTBE. Other extraction solvents' efficiency is in order of MTBE>Dichloromethane>n-Hexane>Diethylether. The optimum NaCl dosage for increasing efficiency is 5 g in liquid-liquid extraction method. The shaking time(0~24hr) has no concern with adsorption efficiency. The optimum adsorbent is XAD-2 resin and extraction solvent is MTBE. Dosing NaCl, adsorption efficiency is increased in liquid-liquid extraction method, but NaCl has no effect on liquid-solid extraction method. In this experimental results, this algae toxins(Mycrocystin, Anatoxin etc.).

• Journal of Environmental Science International
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• v.7 no.5
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• pp.615-622
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• 1998

The volatile organic compounds(VOCs) emitted from raw garlic and Kimchee were analyzed with thermal desorption or purge ＆ trap/gas chromatography/mass selective detection method. Very offensive compounds such as methyl allyl sulfide, dimethyl sulfide, dimethyl disulfide, diallyl sulfide, methyl allyl disulfide, diallyl disulfide and dimethyl trisulfide were detected, and among them, dimethyl disulfide and dimethyl trisulfide were confirmed to be generated during the precocity of Kimchee or emitted from the stuff of Kimchee other than the garlic. Malodorous compounds emitted from the garlic or Kimchee were detected in the breath of a Korean and the refregirator keeping Kimchee. It was confirmed that the disufides emitted from the garlic or Kimchee were major components of offensive odor in the alveolar air and the refregirator. It was clarfied that heat process is very effective to reduce odorous VOCs in garlic or Kimchee.

• Analytical Science and Technology
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• v.13 no.3
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• pp.277-281
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• 2000

The solid phase microextrction (SPME) fiber which contains $100{\mu}m$ polydimethyl siloxane of a stationary phase was used for the analysis of volatile organic compounds contained in aqueous solution. sixteen volatile organic compounds, which were spiked in blank water and extracted by the headspace SPME techique, were analyzed by gas chromatography/mass spectrometry (GC/MS). Analytical results showed that the percent of average recoveries and relative standard deviations were 97% and 4.7%, respectively. The value of detection limit was ranged from 0.01 to $0.5{\mu}g/l$. These results are more accurate than those obtained by the other methods such as purge and trap and headspace methods.

• Journal of Korean Society for Atmospheric Environment
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• v.9 no.E
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• pp.373-381
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• 1993

To understand the human exposure levels of volatile halogenated hydrocar-bons in ambient air, a new rapid and convenient analytical method for determination of the compounds in gaseous phase was evaluated and established. The method is based upon passsive diffusion to personal sampler containing adsorbent and solvent extraction followed by purge trap/ on-column cryof-ocusing method. A new method needs no special instrumentation for gas collection because it is based upon the passive diffusion principle. The typical chromatogram obtained in this study proved that rapid and simultaneous determination of target analytes was possible with good resolution. The developed method was successfully applied to determine the volatile halogenated hydrocarbons in indoor air and the values obtained by this new method were compared with those by direct suction method. The concentration of carbon tetrachloride, 1,1,2-trichloroethylene, chloroform showed the values below 400$\mug/m^3$ except the maximum of 1,513$\mug/m^3$ of chloroform. 1,1,1-Trichloroethane showed approximately 1,000 to 5,000$\mug/m^3$ range of diurnal fluctuation in indoor air.