• Korean Journal of Food Science and Technology
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• v.29 no.4
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• pp.745-751
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• 1997

Volatile flavor components of kochujang made from a glutinuous rice by traditional method were analyzed by using purge and trap method during fermentation, and identified with GC-MSD. Fifty-one volatile components including 19 alcohols, 13 esters, 7 acids, 3 aldehydes, 1 alkanes, 2 ketones, 2 amines, 1 benzene, 1 alkene, 1 phenol and others were found in kochujang made by traditional method. The number of volatile components detected immediately after making kochujang were 22 and increased to 41 components after 30 day of fermentation. The most number 51 of volatile components were found after 120 day of fermentation. Twenty-two volatile components were commonly found through the fermentation period such as acetic acid ethyl ester, ethanol, butanoic acid ethyl ester, 1-butanol, 2-methyl-1-propanol, 3-methyl-1-butanol, butanoic acid and ethenone. Peak area(%) of 1-butanol was the highest one among the volatile components at immediately after mashing while ethanol showed the highest peak area after 30 day of fermentation. Although the various types of peak areas of volatile components were shown in kochujang during the fermentation days, acetic acid-ethyl ester, ethanol, butanoic acid-ethyl ester, 1-butanol, 3-methyl-1-butanol and 2-methyl-1-propanol were mainly detected during fermentation. Those might be the major volatile components in kochujang made by traditional method.

• Membrane Journal
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• v.26 no.3
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• pp.197-204
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• 2016

The objective of this work was to investigate the performance of pervaporation process for recovery of ester compounds from model aqueous solutions and how the fluxes of esters and water were affected by changes in feed concentration and temperature. The flux of ethyl acetate (EA), propyl acetate (PA), ethyl propionate (EP), butyl acetate (BA), and ethyl butyrate (EB) increased with an increase in feed concentration from 0.15 wt% to 0.60 wt%, and increased with temperature change from $30^{\circ}C$ to $50^{\circ}C$. The flux of esters (EA, PA, EP, BA, and EB) was in order of (EA) < (PA, EP) < (BA, EB). This result meant that the flux strongly depended on affinity between esters and membrane surface; EA is the least hydrophobic because it has one hydrophobic function group ($-CH_2-$), (PA, EP) have two ($-CH_2-$), and (BA, EB) are the most hydrophobic because these have three ($-CH_2-$). As well as such an influence of hydrophobicity of ester molecules on ester flux, the influence of hydrophobicity of membrane surface on ester flux needs further investigation. With increase in temperature, water flux of aqueous EA, PA, EP, BA, and EB solution increased. However, water flux of aqueous ester solutions did not change appreciably with increase in concentration. This experimental results may be used as fundamental data for pervaporation (PV) to improve the aroma recovery process as an alternative to thermal evaporation and distillation processes.

• Journal of the Korean Society of Food Science and Nutrition
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• v.12 no.3
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• pp.259-263
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• 1983

This experiment was carried out to investigate the effect of pH at coagulation on fatty acid and sterol composition of green LPC. Green juice of Italian ryegrass, red clover, oats and alfalfa was adjusted at pH 4, 6, 8 and heated at $85^{\circ}C$ for ten minutes. Green LPC was taken from the above green juice. The results obtained were as follows. 1. Green LPC of Italian ryegrass, oats and alfalfa contained much on the order of linoleic acid, palmitic acid and linolenic acid. Methyl ester of these three fatty acid accounted for 70.4% to 86.2% of total fatty acid methyl ester. Green LPC of red clover contained much palmitic acid, linoleic acid, and linolenic acid. These three fatty acid methyl ester accounted for 82.5% to 86.2% of total fatty acid methyl ester. 2. Linolenic acid was highest in the green LPC of red clover, oats and alfalfa which was adjusted at pH 8 and heated and coagulated, and next at pH 6, and pH 4, respectively. Linolenic acid was highest in the green LPC of Italian ryegrass which was adjusted at pH 6, next pH 8, and pH 4. 3. Green LPC of red clover and alfalfa contained cholesterol. The all green LPC contained campesterol, stigmasterol and sitosterol. 4. Sterol was highest in the green LPC of Italian ryegrass, red clover and oats which was adjusted at pH 8 and next at pH 4, and pH 6, respectively. Sterol was highest in the green LPC of alfalfa which was adjusted at pH 8, and next at pH 6, and pH 4, respectively.

• Journal of the Korean Society of Food Science and Nutrition
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• v.30 no.5
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• pp.943-948
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• 2001

Green mustard leves were found to effectively prevent lipid peroxidation of bovine-brain tissue by ascor-bate/Fe system, The 50% methanol extracts mustard leaves were separated into four solvent faction using n-hexane,. EtOAc, n-BiOH and water. Then n-BiOH fraction exclusively exhibited the antioxidative activities at concentration above 100 $\mu\textrm{g}$/mL/ The n-BuOH fraction was further isolated to a single compound using TLC analysis and silica gel chromatography. The active antiodidative compounds were identified as sinapic acid methyl ester and ferulic acid methyl ester by $^{1}$H-NMR and $^{13}$ C-NMR, The sinapic acid methyl ester and ferulic acid methyl ester were prepared by methylating of sinapic acid and ferulic acid with diazomethane. The results strongly suggested that sinapic acid and ferulic acid could be emplyed as a potential antioxiative agents for preventing the bovine brain lipid peroxidation. lipid peroxidation.

• Journal of Photoscience
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• v.7 no.4
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• pp.149-152
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• 2000

No Abstract. See Full-text

• Tribology and Lubricants
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• v.6 no.1
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• pp.7-16
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• 1990

본 보에서는 지난호(윤활학회지 Vol.5, No.2 1989. 10)에 이어 synlube 중 ester oil의 제조 및 합성유와 광유와의 물성 비교 결과를 요약하여 기술하였다. 천연 ester oil인 동,식물유가 윤활유로 사용된 역사는 기원전 1600년경 부터이다. 그러나 ester계 합성유는 저온성상 및 윤활성을 향상시킬 목적으로 2차대전 중 독일과 미국에서 연구를 시작하여 1947년 영국에서 diester oil을 turbo-prop 엔진으로 사용하기 시작하였다.

• Journal of the Korean Chemical Society
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• v.47 no.4
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• pp.427-431
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• 2003

• Applied Biological Chemistry
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• v.41 no.8
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• pp.611-612
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• 1998

The transition state analog for metal catalyzed hydrolysis of an ester through cooperative interactions between metal ions as Lewis acid and peroxide was discussed.

• Archives of Pharmacal Research
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• v.18 no.1
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• pp.62-63
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• 1995

• Bulletin of the Korean Chemical Society
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• v.24 no.1
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• pp.13-14
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• 2003