• Korean Journal of Food Science and Technology
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• v.21 no.6
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• pp.869-875
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• 1989

For the evaluation of storage stability of kiwifruit, the conditions of CA storage were based on the following gas compositions; 2% oxygen and 2, 4, 6% carbon dioxide, respectively. The results obtained from the experiment were as follows; The flesh softening was considerably reduced at the storage atmospheres of 4% $CO_2$ plus 2% $O_2$, and fruit firmness of 3.0kg was marked in this CA condition after storage for 180 days. The concentration of $CO_2$ affected clearly on the respiration rate and organic acid compositions of kiwifruit during CA storage. The respiration rate at the storage condition of 6% $CO_2$ was lower than those at 2 and 4% $CO_2$. Quinic and succinic acid contents were obviously increased in the kiwifruit stored at all the CA conditions studied. In comparision of the developed amounts of off-flavor substances, ethanol and acetaldehyde, depended upon the concentration of $CO_2$ in the CA conditions, the larger amount were produced in the storage condition of higher concentration of $CO_3$. From the results mentioned above, it could be concluded that the optimum atmosphere combination for CA storage of kiwifruit was 4% $CO_2$ plus 2% $O_2$.

• Journal of Korean Society for Atmospheric Environment
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• v.22 no.5
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• pp.574-589
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• 2006

Although concentrations of hazardous air pollutants(HAPs) are very low in the atmosphere, a growing attention has been paid on such compounds due to their high toxicity and bioaccumulation potentials into human body. In order to control and manage the amount of these materials in ambient air, it is necessary to construct monitoring system of them and to know the current concentration level of HAPs above all. In this work, a wide range of HAPs has been measured in metropolitan area to recognize the present state of HAPs in this area. The measured concentration of VOCs was higher in order of Jeonnongdong, Jeongdong, and Yangsuri. The regional difference of VOCs concentration was also highest in spring. Its total VOCs was ranged from $15.17{\sim}41.45$ ppb. Benzene $0.43{\sim}2.32$ ppb showed similar concentration level with the result of previous researches in Seoul. This value is a little higher than the average concentration 0.92 ppb for national ambient air quality standards in Japan. The concentration of aldehydes in this study was lower than those of other researches. Previous works in Seoul metropolitan area showed that the concentration of formaldehyde and acetaldehyde were higher than 5 ppb. The concentration of gaseous and particulate PAHs was high in order of winter, spring, and summer More than 90% of PAHs with low molecular weight such as 2-rings and 3-rings PAHs existed in gas phase. On the other hands, PAHs with high molecular weight more than 5-rings PAHs almost existed in particulate. In spring, the concentration of gaseous PAHs was 24.38 $ng/m^3$ in Jeongdong. Among the particulate PAHs, the concentrations of Naphthalene, Benzo(b)fluoranthene, and Benzo(g, h, i)perylene were higher than others. Especially, the concentration of Benzo(a)pyrene, a important carcinogenic pollutant, was highest in winter 0.5 $ng/m^3$ and ranged from 0.03 to 0.3 $ng/m^3$ in spring and summer, which is lower than the monitoring result in 90's. These components were mainly originated from the vehicle exhaust or heating equipment use.

• Journal of Life Science
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• v.28 no.5
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• pp.569-576
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• 2018

This study was carried out to investigate the antioxidative, nitrite-scavenging, alcohol-metabolizing, and anti-inflammatory effects of black-cherry tomato juice (BCTJ) on LPS-induced RAW 264.7 cells. The total phenol content of the BCTJ was $156.83{\mu}g\;tannic-acid-equivalent/ml$. The antioxidative effects of BCTJ were measured using DPPH radical-scavenging activity and SOD-like assay. DPPH radical-scavenging activity of BCTJ was increased in a dose-dependent manner (p<0.05) and was 83.39% at 40%. SOD-like activity of BCTJ was 22.01% at 100%. The effects of BCTJ on alcohol-metabolism were determined by measuring generations of reduced nicotinamide adenine dinucleotides (NADH) by alcohol dehydrogenase (ADH) and acetaldehyde dehydrogenase (ALDH). ADH and ALDH activities were 198.87% and 181.89% at 40%, respectively. Nitric scavenging activities of BCTJ were 85.06%, 58.25%, and 43.68% at pH values 1.2, 3.0, and 6.0, respectively, at 50%. Anti-inflammatory effects were examined in LPS-stimulated RAW 264.7 cells. Nitric-oxide production was reduced to 83.55% by the addition of BCTJ at 10%. These results suggest that black-cherry tomato juice has great potential as a resource for natural health products.

• Korean Journal of Food Science and Technology
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• v.33 no.3
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• pp.366-372
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• 2001

Volatile flavor components in the mash of Takjus prepared by using Aspergillus oryzae nuruk were identified by using Gas Chromatography and Gas Chromatography-Mass Spectrometry. Twenty-four esters, 21 alcohols, 10 acids, 9 aldehydes and 4 others were found in the mash of Takju. Thirty six components including 13 esters and 12 alcohols were detected in the beginning of fermentation. Twenty nine components were more detected after second day of fermentation and 68 components were detected after 12 days of fermentation. Thirty five flavor components including 12 alcohols such as ethanol, 2-methyl-1-propanol, 3-methyl-1-butanol and benzeneethanol, 13 esters such as ethyl acetate, ethyl caprylate, ethyl butyrate and isoamyl acetate, 4 aldehydes and 6 acids were usually detected in the fermentation process. Ethanol was predominantly found in the range of $79.86{\sim}89.54%$ as a major component by using relative peak area. 3-Methyl-1-butanol, ethyl caprylate and benzeneethanol were some of the major volatile components through the fermentation respectively. Peak area of 2-methyl-1-propanol, 1-hexanol, 1-dodecanol, ethyl acetate, monoethyl butanoate, acetic acid and isobutylaldehyde among the same group were higher than other components depending upon fermentation time.

• Korean Journal of Food Science and Technology
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• v.32 no.3
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• pp.691-698
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• 2000

Volatile flavor components in the mash of takjus prepared by using Rhizopus japonicus nuruk were identified by using GC and GC-MS. Twenty-four esters, 19 alcohols, 9 acids, 10 aldehydes and 4 others were found in the mash of takju. Thirty nine components including 14 esters and 12 alcohols were detected in the beginning of fermentation. Seventeen components were more detected after second day of fermentation and 66 components were detected after 12 days of fermentation. Thirty eight flavor components including 12 alcohols such as ethanol, 2-methyl-1-propanol and 3-methyl-1-butanol, 14 esters such as ethylacetate, ethylcaprylate and isoamylacetate, 6 aldehydes and 5 acids were usually detected in the fermentation process. Ethanol was predominantly found in the range of 76.2149-92.1155% as a major component by using relative peak area. 3-Methyl-1-butanol, 2-methyl-1-propanol, ethyl caprylate, 2,3-butanediol and benzeneethanol were some of the major volatile components through the fermentation. Peak area of ethylacetate, diethyl succinate, octanoic acid, acetic acid and isobutylaldehyde among the same group were higher than other component depending upon fermentation time.

• Korean Journal of Food Science and Technology
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• v.7 no.1
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• pp.15-21
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• 1975

Soong-Neung is a Korean traditional beverage served after meals and is made from cooked and roasted rice produced on the bottom of the container during the rice cooking process. The volatiles from the extract of cooked and roasted rice were separated into pyrazine and carbonyl fractions and qualitatively investigated. The pyrazine fraction was characterized by gas chromatography and combined gas chromatography-mass spectrometry and five pyrazines were positively identified. Pyrazine compounds identified are 2-methylpyrazine, 2,3-dimethylpyrazine, 2,5-dimethylpyrazine, 2-ethyl-5-methylpyrazine and 2-ethyl-3-methylpyrazine. Carbonyls were converted to their 2,4-dinitrophenylhydrazones and identified by gas chromatography, combined gas chromatography-mass spectrometry and thin layer chromatography. Acetaldehyde, propionaldehyde, iso-butyraldehyde and iso-valeraldehyde were positively identified in the carbonyl compounds. The aroma of the fractions indentified as 2,3-dimethylpyrazine and 2,5-dimethylpyrazine had a nut-like or roasted cereal-like flavor, which is one of the characteristic flavors of Soong-Neung.

• Food Science and Preservation
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• v.18 no.5
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• pp.811-816
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• 2011

Cryoextraction (a freeze concentration using an instrument) can increase the sugar concentration in grape juice by reducing its water content, similar to the natural freezing of grapes for natural ice wine. In this study, fermentation of freeze-concentrated Campbell Early grape (Vitis labruscana) juice to 36 $^{\circ}Bx$ was carried out using Saccharomyces cerevisiae strains D8 and S13 isolated from Korean grapes. During the fermentation, strains S13 and D8 showed rapid sugar reduction and alcohol production compared with S. cerevisiae Fermivin$^{(R)}$ used as a control. After nine-day fermentation, the residual sugar contents were lower in W13(9.77%) and D8 wine(9.07) than that in Fermivin$^{(R)}$ wine(14.0%). Total acid content was high in the D8>S13>Fermivin$^{(R)}$ wine, in that order. The acetaldehyde content was highest in the D8 wine and lowest in the Fermivin$^{(R)}$ wine, among the three. The methanol content was slightly higher in the S13 and D8 wines than in the Fermivin$^{(R)}$ wine. In the sensory evaluation, the S13 wine exhibited the highest score in flavor and taste among the three wines. Both the two S13 and D8 wines exhibited higher scores than Fermivin$^{(R)}$ wine in overall preference.

• Food Science and Preservation
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• v.21 no.5
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• pp.757-765
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• 2014

Campbell Early grapes were spontaneously fermented with and without sulfiting to investigate the effect of sulfiting on the fermentation characteristics and physicochemical properties of Campbell Early wine. During the fermentation, the increase in the alcohol and the decrease in the soluble solid contents were faster without sulfiting, as was the increase in the yeast viable counts compared to those with sulfiting. However, the final alcohol and soluble solid contents reached similar levels with and without sulfiting. The PCR-RFLP analysis of the yeast in the ITS I-5.8S-ITS II region revealed that the increase in the S. cerevisiae was faster in the initial fermentation stage and reached a slightly higher level in the late stage with sulfiting than without sulfiting. The wine prepared after the fermentation with sulfiting showed higher malic and tartaric acid contents, as well as methanol, acetaldehyde, and n-propanol contents, than the wine prepared without sulfiting. The ethyl acetate content of the wine without sulfiting was 375.5 mg/L, which was 5.3 times higher than that (70.5 mg/L) with sulfiting. In the sensory evaluation, the wine without sulfiting obtained higher scores in flavor and overall preference than that with sulfiting.

• Journal of Life Science
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• v.28 no.10
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• pp.1193-1200
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• 2018

This study investigated the physiochemical properties, antioxidative, nitrite-scavenging, and alcohol metabolism enzyme activities of nectarine vinegar prepared by a traditional fermentation method. The pH of nectarine vinegar was 3.70, the sugar content was $8.87^{\circ}Brix$, and the total acidity was 6.29%. Among organic acids detected, acetic acid was highest at 32.42 mg/ml, followed by lactic acid, malic acid, and succinic acid. Total phenol content of the nectarine vinegar was $121.84{\mu}g$ tannic acid equivalents (TAE)/100 ml. The antioxidative effects of muskmelon vinegar were measured using 1,1-Diphenyl2-picrylhydrazy (DPPH) radical-scavenging activity and superoxide dismutase (SOD) assay. DPPH of nectarine vinegar was increased in a dose-dependent manner, which was 84.47% at 40% concentration. SOD activity was increased in a dose-dependent manner, which was 89.06% at 60% concentration. Nitric scavenging activities of nectarine vinegar were 94.17%, 76.91%, and 20.21% at pH values 1.2, 3.0, and 6.0 at 100% concentration, respectively. The effects of nectarine vinegar on alcohol-metabolism were determined by measuring the generation of reduced nicotinamide adenine dinucleotide (NADH) by alcohol dehydrogenase (ADH) and acetaldehyde dehydrogenase (ALDH). ADH and ALDH activities of nectarine vinegar were increased in a dose-dependent manner, which were 153.61% and 178.20 % at 60% concentration, respectively. These results suggest that nectarine vinegar has great potential as a resource for high quality functional health beverages.

• Korean Journal of Food Science and Technology
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• v.37 no.6
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• pp.944-950
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• 2005

Volatile flavor components of Takjus mash prepared using Aspergillus kawachii nuruk were identified by GC and GC/MS. Twenty-two esters, 20 alcohols, 10 acids, 8 aldehydes, and 3 others were found in Takju mash. Thirty two components including 13 esters and 13 alcohols were detected at beginning of fermentation. Thirteen more components were detected after second day of fermentation, and 63 additional components after 12 days of fermentation. Twenty nine flavor components including 12 alcohols such as ethanol, 3-methyl-1-butanol, 2-methyl-1-propanol, and benzeneethanol, 12 esters such as ethyl acetate, ethyl caprylate, and ethyl butyrate 3 aldehydes, and 2 acids were detected during fermentation. Major volatile components detected during fermentation included 3-methyl-1-butanol, ethyl caprylate, and benzeneethanol. Peak areas of 2-methyl-1-propanol, 1-hexanol, 2, 3-butanediol (D.L), 1-dodecanol, 2-phenylethyl acetate, ethyl acetate, and monoethyl butanoate were higher than those of other components depending upon fermentation period.