• Preventive Nutrition and Food Science
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• v.7 no.3
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• pp.299-304
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• 2002

Volatile flavor compounds in the headspace of swiss cheese whey protein concentrate (WPC) were analyzed by dynamic headspace analyzer, gas chromatography, and mass spectrometer. Sixty one compounds were detected from the headspace of dry WPC and 23 compounds from the headspace of an aqueous solution of WPC. The major components were propanol, hexanal, 2-butanone, 2-pentanone, 2,3-butanedion, 2-propanol, acetic acid, dimethyl disulfide and benzothiazole. An external dynamic headspace sampler, devised for this study, effectively collected volatiles from the headspace of dry WPC and aqueous WPC solutions.

• The Korean Journal of Food And Nutrition
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• v.30 no.2
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• pp.363-370
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• 2017

This study investigated the chemical composition of headspace gas from white-flowered lotus (Nelumbo nucifera Gaertner). Volatile flavor compositions of headspace from white-flowered lotus (floral leaf, stamen, flower stalk, stem) were investigated through the solid-phase microextraction method using polydimethylsiloxane-divinylbenzene fiber. The headspace was directly transferred to a gas chromatography-mass spectrometry. Sixty-three volatile flavor constituents were detected in the headspace of lotus floral leaves, and undecanoic acid (7.81%) was the most abundant component. Fifty-three volatile flavor constituents were detected in the headspace of lotus stamina, and isobutylidene phthalide (7.94%) was the most abundant component. Forty-four volatile flavor constituents were detected in the headspace of lotus flower stalks, and 3-butyl dihydrophthalide (11.23%) was the most abundant component. Fifty-nine volatile flavor constituents were detected in the headspace of lotus stems, and ligustilide (16.15%) was the most abundant component. The content of phthalides was higher in the headspace of flower stalks and stems, while alcohols and acids were the predominant compounds in lotus floral leaves.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2001.09a
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• pp.148-150
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• 2001

Solid-phase microextraction (SPME) was investigated to understand the BTEX extraction behavior of SPME in groundwater. Analytical procedure was conducted In both conventional and headspace mode. And the conventional direct extraction method and the headspace analysis method were compared. Data obtained with direct and headspace SPME were very similar and showed successful results. In headspace analysis, the linearity was better and RSD (relative standard deviation, %) was smaller than direct extraction.

• Korean Journal of Food Science and Technology
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• v.28 no.1
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• pp.197-202
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• 1996

The effects of erythrosine on the oxidative stability of cholesterol in an aqueous model system were studied by depleted headspace oxygen and cholesterol oxidation products (COP). As the oncentration of erythrosine was increased, headspace oxygen depletion, 7-COP and total COP increased during storage at $25^{\circ}C$ for 50 hours under the fluorescent light. As the intensity of fluorescent light was increased, amounts of headspace oxygen depleted and COP formed in an aqueous cholesterol dispersion containing erythrosine also increased. Addition of ${\alpha}-,\;{\delta}-$, mixed-tocopherol and ${\beta}-carotene$ resulted in the enhanced oxidative stability of an aqueous cholesterol dispersion containing erythrosine during the fluorescent light storage.

• Korean Journal of Food Science and Technology
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• v.33 no.1
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• pp.153-156
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• 2001

Traditional static headspace and headspace solid-phase microextraction(SPME) techniques were compared for their effectiveness in the extraction of volatile flavor compounds from the headspace of persimmon vinegar. The adsorption condition of SPME fiber for equilibrated headspace vapor was selected as $80^{\circ}C$ and 20 min. Total FID response for volatiles of persimmon vinegar was exactly higher such as total peak area $18.18{\times}10^6$ in SPMEGC technique than total peak area $1.35{\times}10^6$ in static headspace-GC. The major volatiles in persimmon vinegar were acetic acid, ethyl acetate, 3-hydroxy-2-butanone, ethanol, phenethyl alcohol. From static headspace-GC technique, 3 acids, 3 aldehydes, 5 alcohols, 9 esters and 1 ketone were identified. From SPME-GC technique, total 34 compounds including 6 acids, 7 aldehydes, 6 alcohols, 9 esters, 2 hydrocarbones, 1 ketone, 3 others were detected. Also the ratio for benzaldehyde, phenethylacetate and phenethylalcohol were higher in SPME-GC.

• 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.

• Food Science and Preservation
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• v.13 no.1
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• pp.108-114
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• 2006

This study was conducted to determine the volatile flavor compositions of the essential oil and the headspace of Capsella bursa-pastoris Medicus. Essential oil and headspace from the plant were extracted by simultaneous steam distillation extraction (SDE), and solid-phase microextraction(SPME) methods, respectively. Seventy-two compounds including 28 hydrocarbons, 4 aldehydes, 6 ketones, 16 alcohols, 4 esters, 8 acids, and 6 miscellaneous ones were identified in the leaf essential oil extracted by SDE method Sixty-eight compounds including 26 hydrocarbons, 2 aldehydes, 6 ketones, 17 alcohols, 4 esters, 6 acids, and 7 miscellaneous ones were identified in the root essential oil. According to the instrumental analyses the essential oil, phytol ($21.12\%$ in leaves, $20.94\%$ in roots) was the most abundant compound Alcohols, esters, and acids were main groups of the essential oil. On the other hand, thirty-eight compounds including 18 hydrocarbons, 3 aldehydes, 3 ketones, 9 alcohols, 2 esters, 3 miscellaneous ones were identified in the leaf headspace by SPME. In root headspace, thirty-three compounds including 16 hydrocarbons, 2 aldehydes, 1 ketone, 9 alcohols, 3 esten;, and 2 miscellaneous ones were identified. Hydrocarbons($44.02\%$ in leaves, $56.98\%$ in roots) were the main components of the headspace of Capsella bursa-pastoris Medicus.

• 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).

• Korean Journal of Food Science and Technology
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• v.30 no.2
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• pp.434-438
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• 1998

The antioxidant effects of 700 ppm ginseng extract, 100ppm caffeic acid, ferulic acid, vanillic acid, or ${\alpha}-topherol$ on the 1% linoleic acid aqueous buffer system was studied by measuring malondialdehyde (MDA) and headspace oxygen. The compounds showed antioxidant activities in the following order: $caffeic\;acid{\geq}ferulic\;acid\;>\;{\alpha}-tocopherol$>ginseng extract>vanillic acid, with the oxidation inhibition ratio of 63.5, 62.9, 52.3, 51.2 and 5.6% of the control according to MDA results. The mixture of 100 ppm caffeic acid, 100 ppm ${\alpha}-tocopherol$ and 700 ppm ginseng extract had a high oxidation inhibition ratio of 91.2%. Headspace oxygen results had a similar trend with the MDA results. Headspace oxygen results showed that the antioxidant activities were in order of ferulic acid>caffeic acid>${\alpha}-tocopherol$>ginseng extract>vanillic acid and headspace oxygen contents were 18.56, 17.78, 17.17, 16.65 and 15.95%, respectively.

• Applied Biological Chemistry
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• v.35 no.1
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• pp.36-41
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• 1992

Several commercial cottonseed, corn and rapeseed oils were stored at $60^{\circ}C\;and\;70^{\circ}C$ with daily exposure of fluorescent light for 12 hours and evaluated their rancidity by headspace gas chromatographic analysis of pentanal and hexanal. The data of gas chromatographic analysis was compared with organoleptic flavor evaluation. For headspace gas chromatographic analysis, the volatile compounds were recovered by porous polymer trap and flushed into a fused silica capillary column at $250^{\circ}C$. Twenty-three GC peaks were identified on the basis of relative retention time of reference compounds and gas chromatography-mass spectrometry. The results showed that the contents of pentanal and hexanal were linearly increased during storage. A very simple linear relationship was found between organoleptic flavor scores and amounts of two volatile compounds with very high correlation coefficient. This results suggested the possible implication of pentanal and hexanal as an quality index for rancidity evaluation of cottonseed, corn and rapeseed oils.