• Korean Journal of Food Science and Technology
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• v.31 no.6
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• pp.1465-1470
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• 1999

Aroma was extracted from Applemint(Mentha rotundifolia(L.) Huds) with SDE(simultaneous distillation and extraction), SFE(supercritical fluid extraction) and headspace method and the compounds of aroma were tentatively identified with GC-MS. The functionality of aroma compounds were determined with GC-olfactometry. Total 67 compounds were identified. Among them, 39 compounds were determined from SDE, 42 from SFE and 16 from headspace extract. Many terpene compounds were extracted with SDE and headspace methods but hydrocarbones with SFE. The major constituents of aroma obtained from SDE and SFE, were piperitenone oxide, germacrene-D and trans sabinene hydrate, but those from headspace method were 3-octanol, 1,8-cineol, camphene and benzeneacetaldehyde. Results of sniffing test, determining characteristics and strength of aroma showed that the major constituents of SDE extract were refreshing sweet and apple-like(ethyl-2-methyl butanoate), sweet and fruity-like$({\alpha}-thujene)$, fresh mushroom-like(1-octen-3-ol, 3-octanol), and bitter herb-like$({\delta}-cadidene)$. Major constituents of aroma extracts obtained from headspace method were alcoholic, refreshing sweet and apple-like(ethyl 2-methyl butanoate), unpleasant chemical, and bitter herb and grassy-like(camphene).

• Bulletin of the Korean Chemical Society
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• v.26 no.12
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• pp.1996-2000
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• 2005

Headspace hanging drop liquid phase micro-extraction (HS-HD-LPME) is studied as a novel solvent-based sample pretreatment method for floral volatile aroma compounds. This paper reports on application of the HSHD- LPME combined with GC-MS for the analysis of linalool component emitted from evening primrose flowers. The effect of several variables on the method performance was investigated. Additionally, the separation of enantiomers on a cyclodextrin capillary column was performed to identify chirality of (−)-linalool component. Since the unsurpassed volume of a few micro-liters of solvent is used, there is minimal waste or exposure to toxic organic solvents. This method enables to combine extraction, enrichment, clean-up, and sample introduction into a single step prior to the chromatographic process.

• Applied Biological Chemistry
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• v.34 no.2
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• pp.154-161
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• 1991

An objective method for measuring rancidity in soybean oil was developed based on the volatile contents obtained by headspace gas chromatographic analysis. Apparatus for headspace volatile cold trapping-thermal desorption was described, designed to collect and analyze volatiles of soybean oil. Samples of commercially processed soybean oil were stored under controlled condition and then evaluated for flavor by a eight member trained panel and for volatile contents by headspace gas chromatographic analysis. Twenty-three GC peaks were identified on the basis of relative retention time of reference compounds and gas chromatography-mass spectrometry. The volatile compounds identified were autoxidation products of principal unsaturated fatty acids of soybean oil. The simple linear regressions of flavor score with the pentanal or hexanal contents in aged soybean oil gave correlation coefficient of 0.990 and 0.994. respectively. Pentanal and hexanal contents could be used as a potentially useful index for predicting flavor scores of soybean oil.

• Journal of Korean Society of Environmental Engineers
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• v.37 no.5
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• pp.293-302
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• 2015

Halonitromethanes (HNMs) are one of the most toxic groups of disinfection by-products. Recently, various studies have been fulfilled. An automated headspace-solid phase microextraction (SPME) gas chromatography/electron capture detector (GC-ECD) technique was developed for routine analysis of 9 HNMs in water samples. The optimization of the method is discussed. The limits of detection (LOD) and limits of quantification (LOQ) range from 90 ng/L to 260 ng/L and from 270 ng/L to 840 ng/L for 9 HNMs, respectively. Matrix effects in tap water and sea water were investigated and it was shown that the method is suitable for the analysis of trace levels of HNMs, in a wide range of waters. The method developed in the present study has the advantage of being rapid, simple and sensitive.

• Korean Journal of Food Science and Technology
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• v.33 no.3
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• pp.307-312
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• 2001

Flavor compounds in Neungee (sarcodon aspratus) were extracted by simutaneous distillation and extraction (SDE), supercritical fluid extraction (SFE) and headspace method. Flavor compounds obtained by various extraction methods were analyzed with GC and GC-MS. The funtionality of flavor compounds were determined by aroma extract dilution analysis (AEDA) of GC-ofactometry methods. Fifty one flavor compounds were totally identified in Neungee mushroom. However, the numbers of flavor extracted SDE, SFE and headspace were 33, 26 and 17 respectively. The major flavor compounds obtained by SDE, SFE and headspace were 1-octen-3-ol, 1-octen-3-one, 3-octanone, 2-octen-1-ol, 3-octanol, 1-octanol and benzenealdehyde. As the results of sniffing test, the major flavor compounds were found to be fresh mushroom flavor, wood flavor, refreshing sweet flavor, mold flavor, bitter-mushroom and metalic-flavor.

• Analytical Science and Technology
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• v.13 no.4
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• pp.412-422
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• 2000

The polymeric FAB materials of air shower used in clean room of wafer industry have been outgassed with the dynamic headspace (ca.$100^{\circ}C$) for half an hour, and analyzed using GC-MS. The air in the clean room running air shower was sampled using sorbent tube method, and the organic compounds adsorbed in the sorbent tube were extracted using Soxhlet extraction method, and analyzed using GC-MS. The analytical results from FAB materials of air shower (electric over current relay, acryl plate. polycarbonate window, filter, fan housing, steel galvanized cold plate and canvas buffer) indicated that most of chemicals were originated from polymer fragments of FAB materials. Their analytical results have been compared with those from the air of clean room running air shower. These comparative results could lead to identify whether the sources of trace organic contaminants in clean room air are originated from the polymeric FAB material of air shower.

• Mass Spectrometry Letters
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• v.4 no.1
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• pp.18-20
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• 2013

Headspace solid phase micro-extraction gas chromatography/flame ionization detection (HS-SPME-GC/FID) method was compared with headspace gas chromatography/mass selective detection (HS-GC/MS). Organic solvent-spiked urine as well as urine samples from workspace was analyzed under optimal condition of each method. Detection limit of each compound by HS-SPME-GC/FID was $3.4-9.5{\mu}g/L$, which enabled trace analysis of organic solvents in urine. Linear range of each organic solvent was $10-400{\mu}g/L$, with fair correlation coefficient between 0.992 and 0.999. The detection sensitivity was 4 times better than HS-GC/MS in selected ion monitoring (SIM) mode. Accuracy and precision was confirmed using commercial reference material, with accuracy around 90% and precision less than 4.6% of coefficient of variance. Among 48 urine samples from workplace, toluene was detected from 45 samples in the range of $20-324{\mu}g/L$, but no other solvents were found. As a method for trace analysis, SPME HS GC/FID showed high sensitivity for biological monitoring of organic solvent in urine.

• Bulletin of the Korean Chemical Society
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• v.33 no.5
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• pp.1693-1698
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• 2012

A headspace gas chromatographic mass spectrometric (GC-MS) assay method was developed for the simultaneous determination of methyl tertiary butyl ether (MTBE), $tert$-butyl alcohol (TBA) and benzene, toluene, ethyl benzene and xylene (BTEX) in soil contaminated with gasoline. 2 g of soil sample were placed in a 10 mL headspace vial filled with 5 mL of phosphoric acid solution (pH 3) saturated with NaCl, and the solution was spiked with fluorobenzene as an internal standard and sealed with a cap. The vial was heated in a heating block for 40 min at $80^{\circ}C$. The detection limits of the assay were 0.08-0.12 ${\mu}g$/kg for the analytes. For five independent determinations at 10 and 50 ${\mu}g$/kg, the relative standard deviations were less than 10%. The method was used to analyze fifty six soil samples collected from various regions contaminated with gasoline in Korea. The developed method may be valuable for the monitoring of the analytes in soil.

• Journal of Environmental Science International
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• v.13 no.10
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• pp.903-909
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• 2004

A new method based on solid phase microextraction(SPME), coupled with GC/FID, has been developed for the determination of PCE and TCE in water samples. The experimental parameters affecting the SPME process (i.e, kinds of fibers, extraction time, desorption time, extraction temperature, volume ratio of sample to headspace, salt addition, and magnetic stirring) were optimized. The coefficients of determination ($R^2$) for PCE and TCE were 0.9951 and 0.9831, respectively when analytes concentration ranges from 10 to 300$\mu$g/L. The relative standard deviations were 3.4 and $2.1\%$ for concentration of 10$\mu$g/L(n=5), respectively. The detection limits of PCE and TCE were 0.5 and l.3$\mu$g/L, respectively.

• The Korean Journal of Food And Nutrition
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• v.12 no.4
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• pp.375-379
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• 1999

Volatile components of Cornsilk(Zea mays L.) were isolated by purge and trap headspace method and were analyzed by GC and GC/MSD. A total of 44 components were identified in the cornsilk volatile coponents including 9 alcohols 7 aldehydes and ketones 14 terpenes and terpene alcohols 3 pyrazines 5 hydrocarbons and 6 miscellaneous components. The major components were 2-propanol(8.08%) pen-tanol(1.82%) hexanol(2.86%) hexanal(3.68%) heptanal(7.40%) nonanal(7.93%) decanal (2.04%) $\alpha$-copaene(2.20%) limonene(1.68%) $\alpha$-selinene(1.03%) $\beta$-selinene(1.03%)