• Analytical Science and Technology
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• v.28 no.6
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• pp.436-445
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• 2015

Amomi Fructus with anti-oxidative activity was chosen and essential oil was obtained by SDE (simultaneous distillation extraction), and 39 constituents were determined by GC-MS (gas chromatography-mass spectrometry). Major components were camphor, borneol acetate, borneol, D-limonene and camphene. Three solvent extracts such as hexanes, diethyl ether and methylene chloride from Amomi Fructus were obtained. These were analyzed by GC-MS and 4 more constituents were identified in addition to 39 components discovered in essential oil. Five major components such as camphor, borneol acetate, borneol, D-limonene and camphene were also detected, however the relative peak percents of those components were different from those of constituents in essential oil. To estimate the kind and the amount of materials evaporated at certain temperature and conditions from essential oil and solvent extracts, dynamic headspace apparatus was used and materials evaporated and trapped at certain conditions were analyzed by GC-MS. Recovery yield of SDE method from Amomi Fructus was measured by using camphor and standard calibration solution of camphor methanol solution and, the yield was 82.0%. Content of Hg was measured by mercury analyzer and contents of Cd, Pb, Cr, Mn, Co, Ni, Cu and Zn in Amomi Fructus, essential oils and solvent extracts were determined by ICP-MS (Inductively coupled plasma-mass spectrometer). Pb, Cd and Hg were measured in the concentration of 0.72 mg/kg, <0.10 mg/kg and 0.0023 mg/kg, respectively and these were below permission level of purity test. Contents of Mn, Cu and Zn in Amomi Fructus were 213 mg/kg, 8.29 mg/kg and 31.0 mg/kg, respectively and which were relatively higher than other metals such as Cr, Co and Ni. Metals such as Mn (0.65 ~ 9.08 mg/kg), Cu (1.16 ~ 4.40 mg/kg) and Zn (1.10 ~ 3.80 mg/kg) in essential oil and solvent extracts were detected. At this point it is not clear that the metals were cross-contaminated in the course of treating Amomi Fructus or metals were contained in Amomi Fructus. The influence evaluation toward biological model study of these metals in essential oil and solvent extracts will be needed.

• Journal of the Korean Wood Science and Technology
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• v.48 no.5
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• pp.591-607
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• 2020

This study was aimed to investigate the changes of chemical composition of the volatile organic compounds (VOCs) emitted from red pine needles in the process of needle abscission or senescence. The VOCs in intact, senescent, and litter red pine needle samples were analyzed by headspace-solid phase microextraction gas chromatography-mass spectrometry (HS-SPME-GC/MS). And then, multivariate statistical interpretation of the processed data sets was conducted to investigate similarities and dissimilarities of the needle samples. Principal component analysis (PCA) and orthogonal partial least squares discriminant analysis (OPLS-DA) were used to investigate the dataset structure and discrimination between samples, respectively. From the data preview, the levels of major components of VOCs from needles were not significantly different between needle samples. By PCA investigation, the data reduction according to classification based on the chlorophyll a / chlorophyll b (Ca/Cb) ratio were found to be ideal for differentiating intact, senescent, and litter needles. The following OPLS-DA taking Ca/Cb ratio as y-variables showed that needle samples were well grouped on score plot and had the significant discriminant compounds, respectively. Several compounds had significantly correlated with Ca/Cb ratio in a bivariate correlation analysis. Notably, the litter needles had a higher content of oxidized compounds than the intact needles. In summary, we found that chemical compositions of VOCs between intact, senescent, and litter needles are different each other and several compounds reflect characteristic of needle.

• Food Science of Animal Resources
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• v.33 no.5
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• pp.646-654
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• 2013

In this study, quantitative analysis of major volatile flavor compounds from yogurt was conducted using headspace-solid phase microextraction (HS-SPME) GC-FID analysis technique, and the changes of volatile aroma compounds during the storage period were evaluated. The yogurt was prepared with the addition of 2% cereals, such as, white rice (WR), brown rice (BR), germinated brown rice (GBR) and saccharified germinated brown rice (SGBR). After fermentation, the products were stored at $5^{\circ}C$for 15 d. The major volatile aroma compounds in yogurt, such as acetaldehyde, acetone, diacetyl and acetoin were able to be extracted using HS-SPME technique efficiently. The regression ($r^2$) value of standard curve prepared with various concentrations of individual flavor chemicals was analyzed over 0.9975, and reproducibility was acceptable to apply quantitative analysis. The analysis of volatile components of control sample during storage showed that the acetaldehyde on 0 d was 10.83 ppm, and that contents were increased to 15.67 ppm after 15 d of storage. However, addition of BR, GBR and SGBR decreased the acetaldehyde contents during storage periods. The acetone content of all treatments during storage was not significantly different. The diacetyl content of all treatments were increased during storage and the addition of SGBR showed the highest amount of diacetyl (0.84 ppm) among treatments on 15 d of storage. The acetoin content of yogurt added with grains was higher than that of control during storage. As a result, the content of volatile aroma compounds in yoghurt during storage period could be analyzed HS-SPME extraction technique effectively, and HS-SPME/GC analysis can be considered for quality control of fermented milk products.

• Analytical Science and Technology
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• v.25 no.6
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• pp.395-401
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• 2012

This study presents a method for the quantitative analysis of residual vinyl chloride monomer (VCM) in PVC products. In elution solvent, the extraction efficiency was similar by ethanol, THF, and acetone, but using n-hexane, it indicated relatively low extraction efficiency. Measuring VCM in the pulverized PVC samples, it showed reasonable results in both the direct injection method and headspace method with GC/MS. Regarding analysis of VCM in the intermediate sponge samples, five laboratories showed good results, and from the results, it was considered that VCM quantitative method in this study was reliable.

• Korean Journal of Food Science and Technology
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• v.41 no.5
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• pp.509-514
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• 2009

The effectiveness of a technique for binding rice-washed solution with trimethylamine (TMA) was investigated in this study. The mixtures of TMA and rice-washed solution were quantified using an electronic nose based on the mass spectrometer. After 7 min of reaction in a model system, the binding of TMA to the rice-washed solution was detected. As the concentration of rice-washed solution increased, the levels of TMA detected in the headspace decreased, thereby indicating an increase in the binding of TMA to the rice-washed solution. The binding effect of the rice-washed solution was comparable to those of starch, ${\alpha}$-cyclodextrin, or amylose, and superior to that of flour. The results of this study demonstrate the potential for reduction of off-flavors using the rice-washed solution.

• Korean journal of food and cookery science
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• v.14 no.5
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• pp.541-546
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• 1998

Volatile flavor components in leaf and petiole of fresh Pleurospermum kamtschaticum H$\_$OFFM/ were extracted by SDE (simultaneous steam distillation and extraction) method using diethyl ether as solvent. Essential oils were analyzed by gas chromatography (GC) and combined gas chromatography-mass spectrometry (GC-MS). Identification of volatile flavor components was based on the Rl of GC and mass spectrum of GC-MS. A total of 31 components, including 15 hydrocarbons, 4 aldehydes, 1 ketone, 5 alcohols, 2 esters, 3 acids and 1 oxide were identified in the essential oils. (Z)-${\beta}$-Farnesene, (Z, E)-${\alpha}$-farnesene and farnesene were the major volatile flavor components in fresh Pleurospermum kamtschaticum. Volatile flavor patterns of Pleurospermum kamtschaticum were analyzed using electronic nose. Sensor T30/1 and PA2 that were sensitive to alcohols had the highest resistance for fresh Pleurospermum kamtschaticum. Resistance of six metal oxide sensors was decreased in dried sample compared with fresh one.

• The Korean Journal of Food And Nutrition
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• v.26 no.1
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• pp.44-50
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• 2013

Quantitative analyses of naturally occurring methanol were performed for the alcoholic beverages commonly consumed in Jecheon, Chungbuk province, South Korea. The headspace analysis method was optimized for the low and high alcoholic beverages. The external standard method was applied due to the overlapping of 2-propanol and 2-butanol (the internal standard candidates) with target sample matrix peaks. The target samples were selected based on the retail sales amounts of alcoholic beverages in the largest retailer food-mart chain, Jecheon, Chungbuk province, South Korea. There was no sample containing methanol over 0.5 $mg/m{\ell}$, the Korean maximum level of methanol in alcoholic beverages (1.0 $mg/m{\ell}$ for fruit originated liquor etc). The total exposure amount of methanol via alcoholic beverages was estimated based on the daily alcohol consumption of 40 g. The hazard indices calculated by methanol RfD 0.5 mg/kg bw day (US EPA) and ADI 20 mg/kg bw day (proposed by Lachenmeier etc.) were 0.301 and 0.008, respectively. As with the hazard index, aggregate exposures below a HI of 1.0 will likely not result in adverse noncancer health effects over a lifetime of exposure. Then the methanol exposure via the alcoholic liquours might not hazard to Jecheon citizen.

• Korean Journal of Food Science and Technology
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• v.37 no.4
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• pp.532-536
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• 2005

GC-NPD analysis was performed on residues of aluminium phosphide in raw wheat and wheat products by trapping gaseous phosphine in the headspace of vessel. In Australian wheat, over 95% of samples were detected below 1 ppb, considered as safe level, whereas in American wheat, about 70% of 58 samples were detected within 1-10 ppb with 4 showing over 10 ppb. About 14-22% phosphine residues of raw wheat were retained after milling process. Wheat samples of same origin showed significant varying levels of phosphine.

• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.5
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• pp.917-920
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• 2004

The migration potential of volatile organic solvents widely employed in the printing process of food packaging was investigated by using a closed experimental system, which contained a food sample and a paper sheet spiked with the contaminant solvents. The studied organic compounds included toluene and p,m,o-xylene which are relatively highly volatile. Typical food samples of caramel, beef jerky and butter were selected based on their chemical composition and were assigned to the migration system at 10, 25 and 4$0^{\circ}C$. The equilibrated migration level was very high with almost complete transfer in the butter with high fat, while caramel of high carbohydrate content and beef jerky of high protein showed migration degree of 37∼56% and 37∼77%, respectively. Temperature did significantly influence the migration on beef jerky with higher level at higher temperature. There was no difference in the migration level among the solvents.

• Korean Journal of Food Science and Technology
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• v.41 no.6
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• pp.603-608
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• 2009

In this study, "Hongro" apples for test samples were selected from a market for aroma analysis. Analysis was done after 1 hr, in a forming headspace while maintaining a temperature of $25^{\circ}C$. First, the complex aroma of the apples was assessed by a Direct Sensory Method. Secondly, the complex aroma was analyzed under individual aroma conditions separated by GC/FID/Olfactometry. Finally, aroma component analysis by GC/MS was performed. Degrees of contribution of aroma components were evaluated by an aroma value calculation considering aroma duration time, frequency, and intensity. The contribution rate (%) of the aroma induction component influencing apple aroma was determined by aroma component analysis and aroma contribution degree. As a result, it was found that the top four components were as follows, by contribution rate (%): acetic acid (23%), 1-hexanol (16%), butyl ethanoate (13%), 4-methoxy-2-methylbutane (9%). These four components constitute the complex aroma tested by the direct sensory method, and was largely recognized by the apple aroma test panel. Consequently, it was found that these components are the key factors in apple aroma. If the mechanism of formation of these components can be found, it could have a significant influence on consumers' acceptance of new varieties of apples.