• Journal of the Korean Society of Food Science and Nutrition
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• v.30 no.6
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• pp.1011-1020
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• 2001

Volatile organic components from onions stored in the different decay conditions were extracted by SDE apparatus and analyzed by GC-FID and GC/MS. Components of 115, 143, 123 and 137 were identified in fresh onions, decayed onions without heating, half-decayed and complete-decayed onions after heating, respectively. These components included esters, aldehydes, ketones, alcohols and sulfur-containing compounds. Dimethyl trisulfide, dimethyl disulfide, dipropyl trisulfide and 3,5-diethyl-1,2,4-trithiolane were the main sulfur-containing components in fresh onions and decayed onions without heating. As spoilage of onions, the concentrations of sulfur-containing components of volatile extracts significantly decreased. Apart from sulfur-containing components, volatile organic components in half-decayed and complete-decayed onions after heating were mainly composed of esters, aldehydes, ketones and alcohols. Ketones of volatiles in complete-decayed onions after heating were high relatively.

• Journal of the Korean Chemical Society
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• v.25 no.1
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• pp.30-37
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• 1981

A simple micro-sampling system is described which facilitates isolation and concentration of complex organic constituents into three fractions of different volatilities. The method involves the headspace trapping of very volatile components from a complex matrix onto a porous polymer, Tenax GC, followed by the solvent elution of the matrix and the subsequent fractions of the eluate into volatile and less-volatile fractions. The headspace and the volatile fractions are then analyzed by high-resolution capillary gas chromatography. The less-volatile fraction is analyzed by high-performance liquid chromatography. Experimental details and the results obtained using tobacco leaves as a complex organic matrix are presented.

• Food Science and Preservation
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• v.17 no.1
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• pp.151-159
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• 2010

Changes in volatile organic compounds were investigated during storage after electron beam irradiation. Grapes were irradiated at 0.25, 0.5, 0.75, and 1.0 kGy and stored for 1 month at $4^{\circ}C$. Butanol, hexanal, [E]-2-hexenal, hexanol, and 3-methyl-butanol were the major volatile organic compounds of grapes. The types of volatiles in irradiated grapes were similar to those of non-irradiated samples but concentration differed among treatments. Some volatile compounds decreased during storage, whereas others, especially the esters, increased. Concentration of most volatile compounds were higher in pre-stored grapes than in post-stored fruit (thus, during the 30 days after irradiation by e-beam). Consequently, concentration of volatile organic compounds either increased or decreased after e-beam irradiation but these changes did not correlate with irradiation dose.

• Analytical Science and Technology
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• v.7 no.1
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• pp.125-132
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• 1994

Flavours in kimchee are the result of unique combination of various sugars, organic acids and amino acids as well as various volatile organic compounds including sulfur-containing compounds, terpenes, alcohols, and some volatile organic acids. In the experiment for the flavour extracting methods, dynamic headspace(DHS) is more effective for collection of volatile flavour than simultaneous distillation extraction(SDE). The best polarity available at the moment is 5% phenyl methyl poly-siloxane which will separate non-polar, intermediate and polar components with good resolution.

• Food Industry And Nutrition
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• v.7 no.2
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• pp.40-44
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• 2002

매실의 향기성분은 50여종 중 알콜류가 benzyl alcohol, linalool, 1,6-octadien-3-ol, n-haxanol 등 10종, aldehyde류가 2-hexenal, benzaldehyde, n-hexanal 등 3종, acid류가 butandeionic acid, acetic acid, 2종, 2-iodo-hexane 등 hydrocarbon류가 5종, butanedioic acid-diethyl estet를 포함한 ester류가 3종, B-ionone을 포함한 ketone류가 3종 그리고 기타 성분이 2종이었다. 매실이 성숙함에 따라 향기성분의 수가 증가하고 그 함량도 증가하는 경향이었다. 매실의 비휘발성 유기산의 조성은 succinic, fumaric, oxalic, malic, tartaric 및 citric acid이었다. 매실이 비휘발성 유기산은 성숙 초기에는 malic acid와 oxalic acid의 함량이 높았다. Citric acid의 함량이 증가한 반면에 대부분의 유기산은 감소하는 경향이었다. 휘발성 유기산은 성숙중에 formic acid함량은 감소하고 butyric acid의 함량은 증가하는 경향이었다. 총 유기산의 함량은 매실 성숙에 현저히 감소하는 경향이었다.

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2001.05a
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• pp.59-61
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• 2001

휘발성 유기화합물로 오염된 가스 제거를 위한 최적 조건을 찾고자 VOC를 생물학적 처리방법 중 하나인 생물여과기를 이용하여 조사하였다. 100여일 운영 후, 25와 $45^{\circ}C$조건 보다 $32^{\circ}C$조건에서 휘발성 유기화합물의 분해력이 높게 나타났다. 생물여과기는 다양한 휘발성 유기화합물 농도와 EBRT 조건에서 약 100일간 운전되었으며, 최대 제거량 128 $g/m^{3}h$에서 113 $g/m^{3}h$ 임을 알 수 있었다. 휘발성 유기화합물은 체류시간 1～3 min에서 제거율이 30～96%까지 변화하는 것을 보여 주었다. 이상의 휘발성 유기화합물 중 일부는 심각한 환경문제를 야기시키므로 이들 휘발성 유기화합물을 완전 제거하거나 최소화시킬 수 있다면 생물여과 시스템은 안정성과 경제적 측면에서 매우 바람직하겠다. 본 연구 결과는 미생물을 이용한 생물여과법이 효과적인 처리 공정임을 보여주었고 혼합된 휘발성 유기화합물이 존재하더라도 그 성분을 동시에 분해할 수 있다는 결과를 보여 주었다.

• Korean journal of food and cookery science
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• v.9 no.4
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• pp.257-260
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• 1993

For the purpose of supplying the information to improve the acceptability of soy paste as the condi-ment, we investigated the changes of free sugar, volatile and nonvolatile organic acids during improved soypaste fermentation. The results were as follows; Free sugars were increased in order of glc> xyl>ara>gal. Acetic, formic, butyric, and propionic acid in volatile organic acids were detected. And total contents were increased until 60 day. In 180 day, contents of volatile organic acids were high in order of acetic>propionic> butyric> formic. The contents of succinic and glutaric acid in nonvolatile organic acids were predominent and increased in order of succinic>glutaric>lactic. Tartaric>citric>malic acid were produced in the next order.

• Food Science and Preservation
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• v.14 no.3
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• pp.308-314
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• 2007

To investigate effects of fermentation on volatile components, we analyzed volatile organic compounds of raw and fermented Rhus verniciflua S. bark. A 50%(w/v) sugar solution was used for fermentation. Volatile organic compounds of raw and fermented Rhus verniciflua S. were extracted by the simultaneous steam distillation and extraction(SDE) method, with a mixture of n-pentane and diethylether(1:1, v/v) and analyzed by gas chromatograph-mass spectrometer. A total of 51 and 27 volatile organic compounds were detected in raw and fermented samples, respectively, and were mainly alcohols. Compounds such as ethyl acetate, 2-methyl-3-buten-2-ol, 3-methylbutanal, 1-octen-3-o1, 3-methyl-2-butanone, hexanal and pentanal were detected as the primary compounds in the raw sample. The fermented sample showed sour different volatile compounds, such as ethanol, ethyl acetate, ethyl lactate and 3-methylbutanol. Thus, a number of volatile organic compounds were synthesized after fermentation of Rhus verniciflua S. bark.

• Clean Technology
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• v.18 no.2
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• pp.191-199
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• 2012

In order to reduce or remove off-flavor and volatile organic compounds (VOCs) from Laminaria japonica effectively, continuous treatment process by supercritical carbon dioxide (SC-$CO_2$) was applied. After freeze-drying, Laminaria japonica powdered with $710{\mu}m$ was used. Experiments were carried out at temperature range from 35 to $55^{\circ}C$, and pressure range from 10 to 25 MPa for evaluation of SC-$CO_2$ treatment effect. Flow rate of carbon dioxide used in this reseach was constantly fixed at 26.81 g/min. Before and after treatment of SC-$CO_2$, off-flavor and VOCs from Laminaria japonica were analyzed by gas chromatography-mass spectrometry detector (GC-MSD). Total 47 VOCs emitted from Laminaria japonica were identified before treatment of SC-$CO_2$, major components of seaweed smell (ordor) in Laminaria japonica were identified as alcohols, aldehydes, ester and acids, ketone, halogenated compounds and hydrocarbon. Off-flavor and VOCs in all experimental conditions was reduced or removed after SC-$CO_2$ treatment. Among the experimental conditions, the highest removal yield was at 25 MPa and $55^{\circ}C$.

• Korean Journal of Food Science and Technology
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• v.42 no.4
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• pp.407-413
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• 2010

This study was performed to compare the quality and volatile components of two cucumber (Cucumis sativus L.) cultivars (Cheongnakhab, Ipchunakhab)-grown under organic and conventional conditions. The levels of pH and soluble solids in the organic system were similar to those in the conventional system. The hardness of the pulp in the organic cucumbers was slightly higher than that in conventional cucumber regardless of cultivar. However, the contents of chlorophyll a, b, and total chlorophyll in organic cucumbers were significantly (p<0.05) higher than those in conventional cucumber. The major volatile compound of fresh cucumber was (E,Z)-2,6-nonadienal regardless of cultivar and farming system. When classified by the identified components' functional group, the rate of aldehydes was the highest of all samples. The results indicate that the quality and volatile components in organic cucumbers were similar to those in conventional cucumbers except for hardness and chlorophyll contents regardless of cultivar.