• Food Quality and Culture
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• v.2 no.1
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• pp.32-36
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• 2008

This study identified and compared the volatile flavor components of two commercial rice wines: one fermented using the mycelium of Phellinus linteus and a regular commercial rice wine. The volatile flavor components were isolated from the infusions by Porapak Q (50-80 mesh) column adsorption. The concentrated aroma extracts were then analyzed and identified by GC and GC-MS. Thirty-four kinds of flavor components were identified in the mycelium-fermented rice wine, including 11 alcohols, 8 esters, 3 ketones, 6 acids, 3 hydrocarbones, and 4 others. In the regular commercial rice wine, 36 kindss of flavor compounds were identified, including 9 alcohols, 6 esters, 4 ketones, 6 acids, 9 hydrocarbones, and 2 others. Therefore, the data indicate that the primary flavor components in the rice wines were alcohols and esters.

• Korean Journal of Food Science and Technology
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• v.22 no.1
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• pp.44-49
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• 1990

The quality of garlic powder produced by hot all drying and freeze drying method was evaluated Porapak Q column was comparatively profitable for the separation of flavor components in hexane extracts of garlic. Freeze dried (FD) garlic powder had higher diallyl disulphide, total pyruvic acid and alliin than hot air dried (HD) garlic powder. On the results of color evaluation by color difference meter, garlic powder of HD were more brownish than FD. In microstructure of garlic powder observed by SEM, freeze dried garlic powder was fairly porous.

• Analytical Science and Technology
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• v.17 no.6
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• pp.496-513
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• 2004

This study was carried out to evaluate the performance of sampling and analytical methodology used for the measurement of toxic volatile organic compounds (VOCs) in the ambient air. VOCs were determined by the adsorbent tube sampling and automatic thermal desorption coupled with GC/MSD analysis. Target analytes were 33 compounds including major aromatic compounds such as BTEX, and halogenated compounds. The methodology was investigated with a wide range of different adsorbents which are commercially available and have been frequently adopted for the VOC measurement. A total of 10 adsorbents were tested in this study: 6 carbon-based adsorbents such as Carbotrap, Carbopack B, Carbosieve S-III, Carboxen 1000, Carbotrap C, Activated Charcoal; and 4 polymer-based adsorbents including Tenax, Porapak Q, Chromosorb 102, and Chromosorb 106. The sampling performance was evaluated with respect to the sampling capacity of VOCs with single-adsorbent and multiple-adsorbents methods for standard samples and field samples. As a result, the best adsorbents for single-adsorbent method in the sampling of toxic organic compounds (including benzene, toluene, xylenes etc.) appeared to be Carbotrap, Carbopack B and Tenax TA. On the other hand, Chromosorb 102, Chromosorb 106 and Porapak Q were found to be unsuitable adsorbents for VOC measurement based on thermal desorption method. Multi-adsorbent packings were evaluated with 4 carbon-based adsorbents, which classified by 3 combination sets of double adsorbents and 2 combination sets of triple adsorbents. The results indicated that the most suitable combination for toixc VOC measurements is Carbotrap C with Carbotrap. Multi-sorbents tubes packed with a strong adsorbent such as Carbosieve S-III or Carboxen 1000 were found to be relatively unsuitable for several compounds, not only owing to the effect of migration of adsorbed compounds from weaker adsorbent to stronger adsorbent, but to hydrophobic nature of the adsorbents. Therefore, it should be addressed that selection of a proper adsorbent (or combination of multi sorbents) is extremely important to obtain reliable data for the concentrations of toxic VOCs in indoor and outdoor environments.

• Journal of the Korean Chemical Society
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• v.21 no.4
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• pp.293-303
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• 1977

Cellulosic organic solid wastes such as bark and sawdust, and filter papers as a pure cellulose were pyrolyzed at $300^{\circ}C$ under nitrogen current and mixed current of nitrogen and air. Amounts of condensates collected in air, water, and dry ice-acetone cooling traps, noncondensable gases, and carbonized residues were surveyed. The components of volatile liquids condensed in dry ice-acetone trap were separated by means of gas chromatograph and identified by retention times and syringe reactions. Pyrolysis under nitrogen current produced 13.4∼29.6${\%}$ of tar, 0.01∼0.12${\%}$ of aqueous liquids, 0.24∼1.43${\%}$ of volatile liquids, 9.84∼42.41${\%}$ of noncondensable gases, and 44.0∼65.81${\%}$ of carbonized residues. Pyrolysis under mixed current decreased tar and condensable liquids, but increased noncondensable gases.Volatile liquids collected under nitrogen current separated into the same 19 components by Porapak Q column regardless of the materials and only difference among materials was relative amounts of components. Volatile liquids collected under mixed current separated into six components and mainly lower molecular weight compounds such as methanol and formaldehyde were produced. According to the retention times and syringe reactions, methanol, formaldehyde, acetone, acetaldehyde, acetic acid, and three other compounds presumably containing hydroxyl group in the molecular structure were identified out of 19 compounds.

• Journal of the Korean Chemical Society
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• v.38 no.9
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• pp.640-652
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• 1994

This work is undertaken to determine alcohol homologues so-called fusel oil that may be present in the Korean folk sojues (distilled liquor) made from grains and to describe sample preparation and analytical method by GC-FID-MS. Solid phase extraction method for sample preparation by using porous styrene divinyl benzene polymer (Porapak Q) was compared with steam distillation and solvent extraction method. Retention behaviors of homologous series of alcohols were also studied. Log values of retention time, molecular weight, boiling point, and capacity factor of alcohols showed linear correlations to the carbon number of an alcohol, to the oven temperature, and to the dielectric constant. Components such as methyl alcohol, n-propyl alcohol, isobutyl alcohol, isopentyl alcohol, and phenethyl alcohol have been identified. The more amount of isopentyl alcohol than other alcohols are contained in the Korean folk sojues, while that of n-propyl alcohol are contained in Chinese kaoliangchiew. Degree of similarity or dissimilarity and classification of the individual samples were discussed using multivariate statistical analysis(principal components analysis) based on GC data.

• Journal of the East Asian Society of Dietary Life
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• v.22 no.5
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• pp.642-648
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• 2012

In the present study, yakju was developed added with 100~400 g of meoru (Vitis coignetiae). We analyzed the volatile flavor compounds and investigated the sensory properties of meoru yakju. The volatile flavor compounds were isolated from in fusions by Porapak Q column adsorption. The concentrated flavor extract was analyzed and identified by GC (gas chromatography) and GC-MS (gas chromatography-mass spectrometry) analyses. Thirty-five compounds, including five alcohols, nine esters, seven acids, four hydrocarbons, three ketones, and seven other compounds, were identified. The total number and content of volatile flavor compounds in control yakju were the highest, but they decreased as the amount of added meoru increased. On the other hand, yakju containing 200 g of meoru was characterized by the highest content of ester compounds, and it was the most preferred in terms of flavor, color, taste, and over all acceptability. Based on these results, addition of 200 g of meoru to 1,715 g of control yakju was determined to be the optimal condition for making meoru yakju.