• Journal of Korean Society for Atmospheric Environment
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• 제17권E3호
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• pp.101-107
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• 2001

Source profiles were developed for a total of 45 volatile organic compounds (VOC) that can be emitted from gasoline evaporation. The gasoline samples of five major brands (for each season) were blended on the basis of the market share in Seoul area and analyzed by a GC-MS/FID system. In addition, we calculated gasoline evaporative compositions using the Raoult's law from the liquid gasoline compositions. The measured and estimated gasoline vapor compositions agree well each other. As a group, alkanes are the most abundant in the gasoline vapors profiles (77.4% on average), followed by alkenes (19.1%), and aromatics (1.7%). As a specie in gasoline vapor, i-pentane is the most abundant, followed by n-butane, n-pentane, i-butane, trans-and cis-2-butenes, 2-methyl-2-butene, and trans-and cis-2-pentenes . It was also seen that aromatic content was much lower in the vapor phase compositions. From the comparison between experimental and calculated compositions, we identified the fact that once the gasoline vapor composition is reliably constructed entirely from the measured gasoline composition and the Raoult's law calculations, the need for doing separate chemical analyses of the gasoline vapor can be reduced.

• Preventive Nutrition and Food Science
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• 제18권3호
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• pp.218-221
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• 2013

Korean cabbage, a member of the Brassicaceae family which also includes cauliflower, mustard, radish, and turnip plants, is a crucial leafy vegetable crop. Korean cabbage is harvested after completion of the leaf heading process and is often prepared for use in "baechu kimchi", a traditional Korean food. Many of the components in Korean cabbage are essential for proper human nutrition; these components can be divided into two groups: primary metabolites, which include carbohydrates, amino acids, fatty acids, and organic acids, and secondary metabolites such as flavonoids, carotenoids, sterols, phenolic acids, alkaloids, and glucosinolates (GSLs). Using gas chromatography-mass spectrometry, this study examined the variety of volatile compounds (including isothiocyanates) contained in Korean cabbage and its seed, which resulted in the identification of 16 and 12 volatile compounds, respectively. The primary volatile compound found in the cabbage was ethyl linoleolate (~23%), while 4,5-epithiovaleronitrile (~46%) was the primary volatile component in the seed.

• 한국환경과학회지
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• 제25권8호
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• pp.1207-1212
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• 2016

The objectives of this study were to evaluate the effect of replacing 40% corn meal with three different types of barley (Youngyang, Wooho, and Yuyeon) on the chemical compositions, microbial indices, gas emission, and volatile fatty acid (VFA) content in feces of growing pigs. Sixteen pigs (Landrace ${\times}$ Yorkshire ${\times}$ Duroc) with an initial average body weight of $71{\pm}2kg$ were maintained in metabolic cages and randomly allotted to four treatments containing different sources of barley, for 23 days. The treatment with three different barley types replacing 40% ground corn showed no effect (P>0.05) on fecal chemical compositions, microbial indices, gas emission, and VFA. However, some differences (P<0.05) were noted in the chemical compositions of crude fiber and ash, and in the levels of Lactobacillus and Salmonella in the feces of the growing pigs. In conclusion, methane and hydrogen sulfide decreased by replacing 40% corn meal with Youngyang and Wooho barley, respectively.

• 한국식품영양학회지
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• 제30권2호
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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.

• 한국작물학회지
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• 제44권2호
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• pp.154-158
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• 1999

Volatile flavor compounds from perilla leaves were extracted and analyzed with different methods, head-space analysis (HS), simultaneous steam distillation and extraction (SDE) , and solvent extraction (SE), and to compare their efficiencies for quick analysis. Over 30 volatile compounds were isolated and 28 compounds were identified by GC/MSD. Major compound was perillaketone showing the compositions of which were 92% in SDE method, 86% in headspace analysis, and 62% in solvent extraction method. For quick evaluation of leaf flavor in perilla, it was desirable because the headspace analysis method had a shorter analyzing time and smaller sample amount than the other methods.

• Asian Journal of Atmospheric Environment
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• 제12권2호
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• pp.178-191
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• 2018

The concentrations and chemical compositions of volatile organic compounds (VOCs), including volatile fatty acids, phenols, indoles, aldehydes, and ketones, which are the main organic compounds generated by swine, were investigated in July and October 2016 and January 2017. In addition, the emission rates and annual emissions of these components from the swine shed were estimated. The concentrations of VOCs in the swine shed averaged $511.3{\mu}g\;m^{-3}$ in summer, $315.5{\mu}g\;m^{-3}$ in fall and $218.6{\mu}g\;m^{-3}$ in winter. Acetone, acetic acid, propionic acid, and butyric acid were the predominant components of the VOCs, accounting for 80-88% of the total VOCs. The hourly variations of VOC concentrations in the swine shed in fall and winter suggest that the VOC concentrations were related to the ventilation rate of the swine shed, the activity of the swine, and the temperature in the swine shed. Accordingly, the emission rates of VOCs from the swine shed were $1-2{\times}10^3{\mu}g(h\;kg-swine)^{-1}$.

• 한국식생활문화학회지
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• 제22권1호
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• pp.83-90
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• 2007

The changes of the color, texture and volatile flavor compounds of Yu-gwa were investigated that affected by the oxidation during storage to characteristic Yu-gwa quality. Among the proximate compositions, carbohydrate was the most abundant component, and followed by lipid and moisture. Although the change of the color showed different pattern by the packaging materials during the storage period, the value of yellowness(b) increased but that of lightness(L) decreased dramatically after 3 month storage. In the textural properties reported closely related with the moisture content, hardness was fairly affected on the period of the storage rather than the type of packaging materials. The flavor compounds of Yu-gwa were analyzed to evaluate the change of distinct volatile compounds during storage. Of the twenty one separated volatile compounds, major volatiles were aldehydes, alcohols and alkenes. The results also showed that polyethylene(PE) contained less volatiles than polypropylene(PP) by the oxidation process during storage.2,4-Decadienal was gradually increased with the period of the storage, whereas octane and furan were decreased. The results provided that the change of the flavor distribution during the storage, and also the possibility of the volatiles such as hexanal, nonanal and 2,4-decadienal as the indicator for the oxidation process.

• 한국축산식품학회지
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• 제34권2호
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• pp.166-171
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• 2014

The aim of this study is to examine the influences of spices on the amounts and compositions of volatile compounds released from cooked beef patty. Beef patty with 0.5% of spice (nutmeg, onion, garlic, or ginger powder, w/w) was cooked by electronic pan until they reached an internal temperature of $75^{\circ}C$. A total of 46 volatile compounds (6 alcohols, 6 aldehydes, 5 hydrocarbons, 6 ketones, 9 sulfur compounds, and 14 terpenes) from cooked beef patties were detected by using purge-and-trap GC/MS. The addition of nutmeg, onion, or ginger powder significantly reduced the production of the volatile compounds via lipid oxidation in cooked beef patty when compared to those from the control. Also, the addition of nutmeg and garlic powder to beef patty generated a lot of trepans or sulfur volatile compounds, respectively. From these results, the major proportion by chemical classes such as alcohols, aldehydes, hydrocarbons, ketones, sulfur compounds, and terpenes was different depending on the spice variations. The results indicate that addition of spices to the beef patty meaningfully changes the volatile compounds released from within. Therefore, it can be concluded that spices can interact with meat aroma significantly, and thus, the character of each spice should be considered before adding to the beef patty.

• 한국약용작물학회지
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• 제8권1호
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• pp.49-57
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• 2000

오미자 (Schizandra chinensis Bullion)의 건조방법에 따른 휘발성성분의 변화를 알아보고자 생체시료와 건조시료에 대한 SDE (steam distillation & extraction) 추출분석과 Headspace 분석을 하였다. 건조방법별 오미자의 정유함량은 생체시료에서 0.58%, 냉동건조시료에서 0.60%, 열풍건조 $(60^{\circ}C)$ 시료에서 0.30%를 나타냈다. SDE 추출된 정유의 성분조성을 조사한 결과, 생체시료의 주요 성분은 terpinen-4-ol(9.01%), ${\gamma}-terpinene(7.02%),\;{\beta}-myrcene(7. 55%)$, 기타 sesquiterpene류(28.48%) 등으로 나타났다. 냉동 건조시료의 경우도 비슷한 경향을 보였으나, 열풍 건조시료에서는 ${\gamma}-terpinene(5.40%),\;{\beta}-elemene(8.28%)$, 기타 sesquiterpene류(50.38%)등을 주로 함유하여 열풍건조에 의해 성분 조성이 달라졌다. Headspace 분석의 경우 SDE 분석과는 다른 성분조성을 보였는데 생체시료는 ${\beta}-myrcene(22.05%),\;{\gamma}-terpinen(9.47%),\;{\alpha}-pinene(8.91%)$, sabinene (8.48%) 등이 주성분으로 나타났다. 건조시료의 성분조성은 대체적으로 냉동건조, $(60^{\circ}C)$ 열풍건조, $(80^{\circ}C)$ 열풍건조 순으로 ${\beta}-myrcene,\;{\alpha}-terpinene$ 등은 감소하였고, ${\alpha}-ylangene,\;{\alpha}-pinene$, camphene 등은 증가하는 경향이었다. 건조조건에 따라 정유성분의 함량과 조성 이 SDE 분석과 Headspace 분석 모두에서 변화하였는데, 전반적으로 monoterpene류와 알코올류의 조성은 감소하고 상대적으로 고비점 화합물인 sesquiterpene류의 조성은 증가하는 경향을 나타냈다.

• 한국식품영양과학회지
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• 제22권1호
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• pp.53-57
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• 1993

국내 김치류 가운데 향토식품으로서 연구개발의 필요성이 있는 갓의 비휘발성 유기산, 무기질, 지방산조성 및 섬유소 등에 대한 성분분석 결과는 비휘발성 유기산은 잎줄기보다 잎에 많았으며, 특히 malic acid의 함량이 79.lmg%로서 가장 높았고, citric acid는 23.7mg%로서 잎의 함량이 잎줄기보다 4배 정도 더 많았다. 잎과 잎줄기의 무기질은 칼슘(143.7, 81.3mg%)과 마그네슘(22.7, 14.5 mg%)이 높게 나타났으며, 대체로 잎의 무기질함량은 잎줄기에 비하여 1~1.8배 정도 많았다. 특히 철 (6.9, 7.3mg%)은 다른 십자화과 채소에 비하여 상당히 많았다. 총지질을 구성하는 지방산 조성은 $\alpha$-linolenic acid, palmitic acid 그리고 linoleic acid가 대부분을 차지하며, 불포화지방산의 함량이 포화지방산에 비하여 3.7배 많으며, 잎과 잎줄기의 P/S비율이 각각 4.1과 2.9로서 잎이 1.4배 높았다. 식이성 섬유질 중 펙틴질에 있어서 잎과 잎줄기의 알코올불용성성분 (AIS)은 9.4및 6.7%로서 잎의 AIS함량이 1.4배 많았으며, 잎과 줄기에서 공통적으로 AIS는 열수수용성펙틴(HWSP), 인산염가용성펙틴(HXSP), 염산가용성펙틴(HSP)이 4.1 : 2.8 : 1의 비로 구성되며, HXSP와 HSP의 함량이 크게 차이를 보였다. 또한 총 식이성섬유질의 함량은 잎과 잎줄기에서 각각 1.2와 2.8%를 함유하며, ADF에 비하여 NDF함량이 많았으며, 리그닌이 가장 적었다. 셀루로스는 헤미셀루로스에 비하여 2.1배 많았으며, 대체로 잎줄기에는 잎에 비하여 각 식이성 섬유소의 함량이 약간씩 높았다.