• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.9
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• pp.1529-1536
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• 2004

This study was designed to determine total trans fatty acids (tFAs) content of processed foods commonly consumed in the Korean diet and to prepare the database for the estimation of tFAs intake in Koreans. Total fat and tFAs content was determined by Soxhlet extraction method and attenuated total reflection infrared spectroscopy (ATR-IR), respectively. The tFAs positional isomers were analyzed using GC/MS spectrometer. In margarines, the content of tFAs ranged from 8.27% to 28.53%. Shortenings contained higher levels of tFAs (1.98~11.33%) than lards (1.83~1.96%). The content of tFAs in grilled confectioneries was wide (7.37~26.54%). Instant popcorns contained the highest amount of tFAs. Fried chickens had 0.44 to 14.85% of tFAs and french fries had 5.18 to 27.01% of tFAs. In fried snacks (crispy) and chocolates, tFAs were not detected. The amount of tFAs per serving size was the highest in instant popcorn, followed by french fries, fried snack (tortilla), doughnuts, and grilled confectioneries. TFAs isomer of margarines was mostly C18:1${\Delta}$9t. In shortenings and lards, the most abundant positional isomer of tFAs was C18:1${\Delta}$9t and C18:2${\Delta}$9t ${\Delta}$12t. Correlation coefficient of tFAs content between IR and GC/MS method was $r^2$=0.91.

• Journal of Korean Society for Atmospheric Environment
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• v.7 no.1
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• pp.1-16
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• 1991

In this study, sampling and analytical procedures were evaluated for the determination of ambient levels of atmospheric PAH, both in gaseous and particulate phase. The method involves low-volume sampling and Soxhlet extraction of the filters and Tenax absorbent, followed by a clean-up stage using a silica column prior to analysis by reversed-phase HPLC with wavelength programmable fluorescence and UV detection. A total of 18 PAH were identified and quantified, all of which have been of environmental concern. In order to validate the methodology and to ensure compatibility of the results, the analytical method used for the determination of PAH was evaluated with respect to the efficiencies of extraction and clean-up procedure, HPLC separation, and lower limits of detection. In addition, substrate dependency of PAH recovery was investigated for the two types of fiters, i.e. glass fiber and PTFE filters.

• KSBB Journal
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• v.24 no.5
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• pp.477-482
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• 2009

Anthocyanin and origomeric proanthocyanidin (OPC) fractions showing antioxidizing activity are present in grape extracts. Grape extracts are widely used in cosmetic applications as functional ingredients. The aim of our study is to isolate the antioxidant fraction from waste of grape products. The extraction was done using soxhlet apparatus. Next, the extraction was subjected for identification of antioxidants by using HPLC. Antioxidant assay was performed by using 2,2-diphenyl-picryl-hydrazyl (DPPH) and superoxide dismutase (SOD) method. Antioxidizing activity was found to be higher in grape seed extract when compared to grape skin extract. Using the extract, a novel formula with multi lamella emulsion structure has been developed and its safety and stability were confirmed by standard protocols.

• Food Engineering Progress
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• v.15 no.3
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• pp.203-208
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• 2011

Effects of particle size and high pressure processing on the extraction rate of oil compounds from soybean powder were evaluated by Soxhlet method using hexane and supercritical fluid extraction (SFE) using $CO_{2}$. SFE was carried out at 4,000 psi and $50^{\circ}C$ for 4 hr. The mean particle sizes were varied from 26.7 to 862.0 ${\mu}m$ by controlling milling time. Saturation solubility increased as the particle size decreased. At large particle size, high pressure processing (HPP) showed higher extraction yield in both hexane extraction and SFE, but, as the particle size decreased, the HPP was irrelevant to the extraction yield in SFE. The higher extraction rate obtained from the smaller particle size. The scanning electronic microscopy of soybean powder treated by HPP showed pores on the surface of the particle. The higher extraction rate and yield from HPP treatment might be due to the less internal resistance of transferring the solvent and miscellar in the solid matrix by collapsing of tissues.

• Applied Biological Chemistry
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• v.4
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• pp.23-28
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• 1963

Various species of the genus Capsicum contain in their fruits an intensively sharp and pungent substance, Capsaicin, which was first isolated in an almost pure state by Thresh. Containing the pungent principle, Capsicums are used extensively in food as a spice and in medicine as a rubefacient and carminative. Numerous methods have been proposed for the isolation, the chemical structure and the quantitative determination of Capsaicin. Modifying the several methods described before, the Capsaicin contents in various species of the genus Capsicum were determined as follows. (1) The isolation of pure Capsaicin was the essential first step for the determination of Capsaicin contents. Powdered cayenne pepper was extracted with acetone. By the method of ether alkali partition extraction slightly modified at this laboratory and by the recrystallization with light petroleum ether that was repeated ten times, the pure crystalline Capsaicin was obtained. Using this Capsaicin, the standard absorption curve was drawn with Beckman spectrophotometer model DU for the quantitative determination of Capsaicin. 92) The powdered sample was extracted in a Soxhlet extractor with ether-acetone solvent system(3:1) for 25 hours. Capsaicin in this ether-acetone extracts was efficiently separated in a pure state by paper partition chromatography using 58% methanol solution as developing agent. It was found that 58% methanol was one of the most valuable solvent to separate Capsaicin from impurities such as sterols, fatty acids, waxes and carotenoid pigments. (3) The colorimetric method modifying the Schulte-Kruger's method which consists of measuring the red color produced with diazobenzenesulphonic acid was used. Capsaicin in various species of the genus Capsicum was determined quantitatively with use of Beckman spectrophotometer model DU at $480\;m{\mu}$.

• Analytical Science and Technology
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• v.36 no.6
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• pp.291-299
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• 2023

The benzo[a]pyrene in edible oils is extracted using methods such as Liquid-liquid, soxhlet and ultrasound-assisted extraction. However these extraction methods have significant drawbacks, such as long extraction time and large amount of solvent usage. To overcome these drawbacks, this study attempted to improve the current complex benzo[a]pyrene analysis method by applying the QuEChERS (Quick, Easy, Cheap, Effective, Rugged and Safe) method that can be analyzed in a simple and short time. The QuEChERS method applied in this study includes extraction of benzo[a]pyrene into n-hexane saturated acetonitrile and n-hexane. After extraction and distribution using magnesium sulfate and sodium chloride, benzo[a]pyrene is analyzed by liquid chromatography with fluorescence detector (LC/FLR). As a result of method validation of the new method, the limit of detection (LOD) and quantification (LOQ) were 0.02 ㎍/kg and 0.05 ㎍/kg, respectively. The calibration curves were constructed using five levels (0.1~10 ㎍/kg) and coefficient (R²) was above 0.99. Mean recovery ratio was ranged from 74.5 to 79.3 % with a relative standard deviation (RSD) between 0.52 to 1.58 %. The accuracy and precision were 72.6~79.4 % and 0.14~7.20 %, respectively. All results satisfied the criteria ranges requested in the Food Safety Evaluation Department guidelines (2016) and AOAC official method of analysis (2023). Therefore, the analysis method presented in this study was a relatively simple pretreatment method compared to the existing analysis method, which reduced the analysis time and solvent use to 92 % and 96 %, respectively.

• 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.

• Analytical Science and Technology
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• v.25 no.6
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• pp.410-415
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• 2012

In this study, a fundamental study was conducted to establish the method for quantitative analysis and pretreatment of triclosan, one of the chemicals to be used as bactericides, detergents, and sterilizers. The extraction efficiency of triclosan was the highest when it was extracted by soxhlet apparatus with n-hexane, and it showed a satisfactory result when the samples were analyzed with both GC/ECD and GC/MS. To evaluate the reproductivity of the results, each 30 reference samples made with paper filter and cotton wool was prepared in this study. From the results with high extraction effectiveness, low analysis deviation, and good statistical analysis data, the method for the extraction and analysis for triclosan were resonable for the paper and textile samples applied in this study.

• Proceedings of the Korean Vacuum Society Conference
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• 2016.02a
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• pp.424.1-424.1
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• 2016

태양전지 모듈의 봉지재로 사용되는 EVA(Ethylene-Vinyl acetate)는 외부의 환경으로부터 태양전지를 보호해주는 역할을 한다. 하지만 frame의 실링재나 glass edge 부분의 결함으로 인해 수분이 침투되어 모듈의 내부자재에 영향을 미치게 되며, 모듈의 효율 감소나 수명 단축의 원인이 된다. 이러한 결함을 줄이기 위해서는 EVA의 crosslinking degree, 절연 저항 특성을 향상시키는 것이 중요하다. 이에 본 연구에서는 EVA의 crosslinking degree를 보기 위해 soxhlet extraction method를 이용하여 gel content를 측정하였으며, 라미네이션 과정 중 curing time에 따른 gel content 변화를 확인하였다. 또한 이 실험을 바탕으로 gel content에 따른 절연 저항을 측정하여 EVA의 crosslinking degree에 의한 절연 저항 특성을 확인하였다.

• Analytical Science and Technology
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• v.27 no.4
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• pp.201-212
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• 2014

Polycyclic aromatic hydrocarbons (PAHs) that are carcinogenic and persistent will be restricted in consumer products from December 27, 2015 by EU REACH regulation. Pretreatment using Soxhlet extraction and quantitative analysis by GC-MS were studied to develop the method for analyzing 18 PAHs in consumer products as well as to detect the amounts and the kinds of PAHs in consumer products such as grips of a bag and a hammer, a cable and a plastic sandal. Linearity and precisions were evaluated by analyses of the standard PAH solutions ranging from 0.3125 mg/L to 5.00 mg of each of 18 PAHs. Linearity of resulting standard curves for all 18 PAHs were obtained with $R^2$ above 0.999. Precisions of the retention times and the peak areas were found to be 0.00%~0.05% and 1.16%~3.69% of relative standard deviations, respectively. The recoveries for spiked samples were all around 95%~105% after Soxhlet extration using three different solvents such as dichloromethane, hexane and toluene. The limits of quantitation for 18 PAHs in solutions and polymer samples by GC-MS were evaluated to be 0.327 mg/L (Benzo[ghi]perylene)~0.464 mg/L (Acenaphthylene) and 1.635 mg/kg (Benzo[ghi]perylene)~2.32 mg/kg (Acenaphthylene) based upon dilution factor of 5, respectively. Under the developed analytical method, only trace amounts of phenanthrene were detected in three samples while 15 kinds of PAHs including phenanthrene were detected in a grip of hammer with concentrations of maximum 83.4 mg/kg of Phenanthrene and minimum 8.5 mg/kg of Acenaphthylene. Further studies are needed to decrease the quantitation limit and to check the feasibility of decreasing Soxhlet time as well as to demonstrate cases that the clean up is required.