• Food Science and Preservation
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• v.15 no.6
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• pp.872-877
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• 2008

This study was carried out to provide basic information related to improvement of flavor and consumption of cheonggukjang. Red ginseng cheonggukjang (RGC) and Rubus coreanum cheonggukjang (RCC) extracts were prepared, and their physicochemical characteristics were compared with either general cheonggukjang (GC) or non-fermented boiled soybean (BS). The moisture and crude fat contents were not significantly different among samples. RGC had the highest reducing sugar content and BS had the lowest. The free sugar content of RGC was higher than that of either GC or RCC, and the major free sugars present were glucose, fructose and sucrose. Seventeen free amino acids were detected in BS and cheonggukjang, and the content of free amino acids ranged from 1,233.8 to 2,599.6 mg/100 g. The greatest content of free amino acids was found in RGC. Color L, a and b values were highest in BS and lowest in RCC. The hardness and strength of RGC and RCC were lower than for GC.

• Korean journal of food and cookery science
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• v.11 no.4
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• pp.386-395
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• 1995

This study was carried out to investigate the volatile constituents change according to extraction methods, parts and heating methods. The research results are as follows: 23 kinds of components were extracted by steam distillation method; 8 by head space method; 16 by ether extraction method; 9 by Tenax-GC. This fact indicated that volatile constituents differ depending upon the extracting method. When the volatile constituents were extracted by steam distillation method and analyzed by GC-MSD, the content of the volatile constituents was 41.71 mg％ in the stem and 85.37 mg％ in the leaf. A total of 23 components - 14 kinds of hydrocarbon, 5 of aldehyde, 4 of alcohol- were detected in the stem. A total of 31 components - 21 kinds of hydrocarbon, 5 of aldehyde, 4 of alcohol and 1 of ester were detected in the leaf. The leaf had comparatively more varied volatile constituents than the stem. In the stem, the octanal content was highest and the contents of limonene, sabinene, -terpinene and -myrcene were higher; in the leaf, the content of octanal was highest and the contents of isobicyclogermacrene, limonene, -farnesene, undecaethiol, -terpinene, sabinene, elemene, -myrcen were higher. These were the major volatile constituents of the water d.opwort. The volatile constituent formation changed as the water dropwort was heated. The volatile constituents of the water dropwort heated in 1000 $m\ell$ were the most similiar to those of the raw water dropwort, and volatile constituent content was highest.

• Korean Journal of Plant Resources
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• v.10 no.4
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• pp.314-318
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• 1997

This experiment was carried out to analyze the essential oils from different parts of Perilla frutescens spp. And to know change of the oil content by a diffenent leaf picking time. The analysis of the essential oils was done with gas chromatography(GC),and the results are as follows. Perilla frutescens spp. contained essential oils mostly in their leaves and stems, although their roots also contained the oils. It was suggested that the optimum leaf-picking time of perilla frutescens var. viridis Mak. on the basis of total essential oils was their flowering period around Aug. 24, and that of Perilla frutescens var. for acuta Kudo was Sep. 14. On the basis of perillaldegyde the optium leaf-picking time of Perilla frutescens var. viridis Mak. and Perilla frutescens var. acuta Kudo was Aug. 24. and Aug. 4. respectively.

• Journal of the East Asian Society of Dietary Life
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• v.11 no.6
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• pp.472-478
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• 2001

This study was conducted to investigate the change in volatile flavor components of persimmon leaves during growth. The flavor components of persimmon leaves were analyzed by gas chromatography (GC) and combined gas chromatography-mass spectrometry(GC/MS). The flavor compounds were collected by simultaneous steam distillation and extraction(SDE) method, and were separated and identified resulting in 126 components, including 23 alcohols, 18 aldehydes, 4 esters. 15 acids, 37 hydrocarbons, 14 ketones, 6 phenols. and 9 others in persimmon leaves. The most abundant components of persimmon leaf were alcohols including iinalool. cis-3-hexanal. 1-$\alpha$ -terpineol. 3.7.11.15-tetramethyl-2-hexadecen-1-ol and aldehydes including trans-2-hexanal. nonanal, 2-decenal and hydrocarbons including 1.1-dimethylethyl cyclohexane, 1-methyl-4-(2-methylpropyl) -benzene. During growth, many other components were formed and dissipated after the 20th of June.

• Korean Journal of Food Science and Technology
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• v.26 no.1
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• pp.68-73
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• 1994

An attempt was made to derermine the volatile flavor components of Dioscorea japonica. Essential oils from roots of the samples were isolated by simultaneous steam distillation-extraction(SDE) method using diethyl ether as solvent. Concentrated samples were analyzed by gas chromatography(GC) and combined gas chromatography-mass spectrometry(GC-MS). Fifty nine volatile flavor components, including 35 hydrocarbons, 5 aldehydes, 1 ketone, 9 alcohols, 2 esters, 3 acids and 4 miscellaneous ones were confirmed in the young roots of Dioscorea japonica. Forty two components, including 23 hydrocarbons, 2 aldehydes, 7 alcohols, 1 ester and 8 acids and 1 miscellaneous one were confirmed in the roots of mature stage. ${\sigma}-3-Carene$ and dodecanoic acid were regarded as the most abundant components in young and mature roots repectively. The profile of volatile flavor components was markedly different in young and mature roots of Dioscorea japonica.

• Journal of the Korean Society of Food Culture
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• v.20 no.2
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• pp.214-220
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• 2005

Seasoning oil (SO) for Chinese dish was manufactured from the combination of Maillard reaction for methionine and xylose with autoclaving method. Volatile compounds were determined by GC, GC-MSD for this SO and 3 kinds of seasoning jajang samples which was obtained from restaurant. From this SO 61 kinds-404.92ppm volatile compounds were separated and identified. And from 3 samples of restaurant, 39 kinds-333.52ppm, 42 kinds-330.01ppm, 42 kinds-393.18ppm obtained respectively. Major volatile components of SO were diallyl disulfide, pentane, diallyl trisulfide, t,t-2,4-decadienal and zinngiberene. Those contents were 40.15ppm, 32.32ppm, 19.57ppm, 15.06ppm and 13.23ppm, respectively. Major volatile components in 3 kinds samples were pentane, propenal, hexanal, t-2-heptanal, 2,4-heptadienal, t,t-2,4-decadienal and unknown components. The volatile components of SO were very similar to 3 samples,

• Analytical Science and Technology
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• v.12 no.3
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• pp.248-255
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• 1999

Sewage sludge samples were extracted with dichlomethane by Soxhlet extraction. The extracts were analysed for the endocrine disrupting compounds (EDC), octylphenol(OP), nonylphenol (NP) and bis (2-ethylhexyl)phthalate (DOP) using GC/MS-SIM. In industrial sewage sludge (sample Z-1) the concentration of NP and DOP were respectively $1168{\mu}g/g$ and $1172{\mu}g/g$ whereas in domestic sludge (sample Z-2) the concentration were respectively $10.8{\mu}g/g$ and $80{\mu}g/g$. OP was not detected in Z-2, but detected a small amount in Z-2 of the samples. Environmental EDC have been shown to affect the fertility of range of living organisms, including humans, and the high levels of NP and DOP in industrial sewage sludge could have serious implications for the reproductive health of humans particularly if the compounds entered the human food chain through water or the ingestion of vegetables or animal products.

• Horticultural Science & Technology
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• v.16 no.4
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• pp.503-507
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• 1998

This study was initiated to evaluate genetic relationship among various domestic and exotic pepper accessions using random amplified polymorphic DNA(RAPD) markers. The results suggested that the optimum conditions for PCR with random primers in Capsicum spp. could be obtained with 3mM of $MgCl_2$, 1.5U of Taq. DNA polymerase, 10ng of template DNA, $200{\mu}M$ of dNTPs, 200nM of random primer, and $42^{\circ}C$ of annealing temperature. Sixteen random primers showing high band intensity and reproducibility were selected from 80 random primers. Primers having 70% GC content were more effective in DNA amplification than primers having 60% GC content. The total 93 DNA bands including 71 polymorphic bands and 22 monomorphic bands were obtained with selected 16 random primers for 31 pepper cultivars and lines. About 4.4 polymorphic bands per primer were produced. Similarity coefficients were calculated by using 71 polymorphic bands and dendrogram based on the similarity coefficient showed clear classification of 31 peppers into three Capsicum species of Capsicum annuum, Capsicum chinense and Capsicum chacoense.

• Journal of the Korean Society of Food Science and Nutrition
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• v.24 no.6
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• pp.925-931
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• 1995

Volatile compounds in Cheddar, Emmentaler, Parmesan and Roquefort cheese and cheese aroma were concentrated using a microsteam distillation-extraction apparatus and those compounds were analyzed with GC. The lipase-treated cheese aroma concentrates showed significantly higher level of short-chain free fatty acids than natural ripened cheese. The sensory properties of rancidity was high in Emmemtaler and Parmesan. Acidity and fruitness were shown high score in Roquefort. Correlation of free fatty acids and cheese flavor 'sharpness, rancidity and soapy' appear to be related(r=0.8239, 0.8918 and 0.7503), respectively. Methyl ketones, the most striking flavor components of Roquefort cheese showed high amounts in the series 2-heptanone > 2-nonanone > 2-pentanone > 2-undecanone. And the intensity of the Roquefort taste sensation 'acidity and fruitness' is linearly correlated with the methyl ketone concentrations(r=0.9284, r=0.9659).

• Analytical Science and Technology
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• v.21 no.1
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• pp.53-57
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• 2008

In order to survey the contents of ethyl carbamate in alcoholic beverages, GC/MS-SIM method was used after extraction with dichloromethane in solid phase extract cartridge contained alcoholic beverages. In the applied GC/MS-SIM method, the values of recoveries and relative standard deviation were ranged from 85.2 % to 87.9 % and from 0.7 % to 1.9 %, the limit of detection and quantification were $2{\mu}g/kg$ and $10{\mu}g/kg$. Depending on alcoholic beverage kinds, the levels were variable and the average level was $194{\mu}g/kg$ for liquor, $105{\mu}g/kg$ for fruit wine, $62{\mu}g/kg$ distilled spirit, $28{\mu}g/kg$ for sake, $15{\mu}g/kg$ for yakju, $12{\mu}g/kg$ for other alcohol beverages, ND for soju, respectively.