• Korean journal of food and cookery science
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• v.24 no.4
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• pp.542-548
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• 2008

In this study, the degree of rancidity and trans fatty acids formation was assessed in Soybean oil(SBO), Corn germ oil (CGO), Canola oil(CNO) and Olive oil(OLO). All samples treated under various conditions were analyzed in order to determine their physicochemical characteristics(RI: Refractive index, Tocopherol, AV: Acid Value, IV: Iodine Value) and total trans fatty acid contents via GC. The results were as follows: The AV of corn germ oil was the highest (0.49$\pm$0.01 and 0.72$\pm$0.04 respectively) among the 4 kinds of oils at $170{\pm}2^{\circ}C$ and $210{\pm}2^{\circ}C$. The IV of olive oil was the lowest(88.7$\pm$0.6 and 89.2$\pm$0.5) among the 4 kinds of oils at $170{\pm}2^{\circ}C$ and $210{\pm}2^{\circ}C$. The trans fatty acid contents of the soybean oil, corn germ oil, canola oil and olive oil, respectively(in g/100) increased from 0.41, 0.60, 0.44 and 0.11 prior to heating to 0.84, 1.36, 0.94 and 0.81 after 7 hours. Catechin and BHT reduced trans fatty acid formation by 0.5-15.5% under all treatment conditions. In particular, Catechin exerted a more profound inhibitory effect on trans fatty acids formation than that did BHT.

• Korean Chemical Engineering Research
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• v.49 no.4
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• pp.480-484
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• 2011

In this study, degumming process was carried out for reducing to less than 10 ppm of phosphorus contents and primary properties of crude canola oil including 0.64 mgKOH/g of acid value, 0.09% of water contents, 0.13% of insoluble impurities, and 40 ppm of phosphorus contents. Efficiency of water degumming and enzymatic degumming was compared for the selection of suitable process obtaining feedstock of biodiesel. Degumming method was determined for preparation of raw material of biodiesel, and reaction conditions were also established. The most effective conditions for water degumming were 2% distilled water (w/w oil), $30^{\circ}C$ of reaction temperature, 900 rpm of agitation speed, and 30 min of reaction time, respectively. In case of enzymatic degumming, optimal conditions were found to be 90 ppm of phospholipase A2 (w/w oil), $50^{\circ}C$ of reaction temperature at pH 5, respectively. When comparing water degumming with enzymatic degumming, efficiency of enzymatic degumming was better than water degumming. However, water degumming method was much more suitable for the production of biodiesel feedstock considering reaction time and process feasibility.

• Korean Journal of Food Science and Technology
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• v.29 no.1
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• pp.15-20
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• 1997

Changes in antioxidative substances-sesamol, sesamin and sesamolin - and mineral contents of sesame oil during refining processes have been studied to investigate the oxidative stability of oils during the storage at $70^{\circ}C$. Fe, Cu, Mg and Zn were nearly removed from the oil by the degumming process. During storage, the changes of total volatile contents in crude and degummed sesame oil were not noticeable but those in alkali-refined and deodorized sesame oil were increased at early period of the storage. The increases of hexanal and pentanal were most noticeable and their concentration was increased markedly in alkali-refined, bleached and deodorized sesame oil at early period of the storage. During refining processes and storage, sesamin was relatively stable but the content of sesamolin was decreased. The content of sesamol was decreased until alkali-refining process but increased during a bleaching process. The content of sesamolin tended to decrease with increasing of sesamol during storage.

• Korean Journal of Poultry Science
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• v.22 no.1
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• pp.31-42
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• 1995

This study was to investigate the effects of dietary linoleic acid(18:2\omega6, LA) and aipha-linolenic acid(18:3\omega3. \alpha-LNA) levels on brain development and fatty acid compositions of various lipid classes in the chicken embryo brain tissues. Thirty two ISA Brown layers, 52 weeks-old, were divided into four groups. Birds of each group were given corn-soybean meal based diets added with 1) safflower oil 8%, 2) safflower oil 6% + perilla oil 2%, 3) safflower oil 2% + perilla oil 6%, or 4) perilla oil 8%. Mter 15 days fed the diets. the layers were artificially inseminated to obtain fertile eggs. During the incubation. embryonic brains were sampled at 15th and 21st days. Fatty acid contents were quantitated by using heptadecanoic acid (17:0) as an internal standard. No significant differences in brain weight and in contents of various lipids such as phospholipid. triglyceride, cholesterol. cholesterol ester and free fatty acid in the tissues were found among the dietary groups (P<0.05). The ratios of AA/LA in the brain lipid classes were lowered as the dietary levels of perilla oil were increased. Higher LA was found in phosphatidylcholine(PC) than arachidonic acid (20:4\omega6. AA), meanwhile the level of LA was less than AA in phosphatidylethanolamine(PE). Docosahexaenoic acid(22:6\omega3, DHA) was the* major fatty acid in the tissue and its content in PE was 2.5~3 times higher than in PC. DHA level in the phospholipid reached at a peak (1.7~1.8 mg/brain) in dietary groups added with 6% or 8% perilla oil. suggesting that no more increase in that fatty acid level in the brain tissue could be obtained by consuming more \alpha-LNA, the major precursor of DHA.

• Journal of Nutrition and Health
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• v.27 no.9
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• pp.901-909
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• 1994

The effects of sardine oil(high in eicosapentaenoic acid : EPA) and tuna oil(high in docosahexaenoic acid : DHA, also high in EPA) on fatty acid composition of brain and learning ability were evaluated in male weanling Sprague-Dawley rats and compared with the effects of corn oil and beef tallow. Animals assigned by randomized block design to one of the four experimental diet groups containing dietary lipid at 15%(w/w) level were given ad libitum for 7 weeks. Food intake and body weight gain of the fish oil groups were significantly lower than those of the corn oil and beef tallow groups. However, brain weights of the groups were not significantly different. In the brain fatty acid composition, the corn oil group showed high concentrations of n-6 fatty acids, the fish oil groups of n-3 fatty acids, and the beef tallow group of saturated fatty acids. Brain EPA and DHA contents of the fish oil groups showed significantly higher than the other groups while the brain ratio of saturated/monounsaturated/polyunsaturated fatty acid was controlled in a narrow range. In a maze test, the fish oil groups appeared to arrive at the goal faster than the corn oil and beef tallow groups. It explained that EPA in diets might efficiently convert to DHA resulting in DHA accumulation in brain tissue and might increase the learning performance as DHA did.

• Korean Journal of Medicinal Crop Science
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• v.20 no.1
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• pp.63-71
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• 2012

The objectives of this study were to investigate the antioxidant activity of Schizandra chinensis seed oil and its active ingredients. Schizandra chinensis seed oil content extracted with hexane was 36.06%. Schizandra chinensis seed oil extracted with hexane was purified during 20 min at $85^{\circ}C$ with phosphoric acid 0.15% for degumming and 20 min at $80^{\circ}C$ with 3 M NaOH 1% for deaciding. The purified oil consisted of unsaturated fatty acid (88.7%), fatty acid (9.97%), and so on. The major unsaturated fatty acids of purified oil were linoleic acid (71.1%) followed by oleic acid (15.7%), while the main saturated fatty acid was palmitic acid (6.56%). The purified oil was found that contents of phenolic compounds, vitamin A, and E were 1.45 g/100 g, 1494.86 RE/100 g, and 0.58 mg ${\alpha}$-TE/100 g, respectively. Schizandra chinensis seed oil exhibited strong antioxidant activity (91.7%) as compared to grape seed oil and canola seed oil with 87.4% and 85.1% in the DPPH assays. Present results suggest that Schizandra chinensis seed oil could be potentially used as bioactive source for health and preventing numerous diseases.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 1989.10a
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• pp.65-70
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• 1989

This paper presents resarch results on the use of a corona detector and a pulse counter in order to diagnose for oil transformers. Using these experimental apparatus, tests were carried out on a typical transformer oil containing different carbonized paper and various moisture contents to measure the picocoulomb val-ues and pulse count. Through the result of this study it was found that the picocoulomb values and pulse count of corona were depended on the getting stained in transformer oil. The amplitude of the partial discharge amount and the number of pulse were decreased up to 70 [。c] and then was increased as the oil temperature goes up. It was concluded that the determinati-on level for diagnosis of oil transform-er was taken into account the temperatu-er of transformer oil, The use of pulse counter method, which have been taken the same property of voltage and temperature variation for the corona measurement mothod, considera-bly increase insulator avilability.

• Transactions of the Korean Society of Automotive Engineers
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• v.4 no.1
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• pp.1-15
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• 1996

This study is concerned with the property changes(chemical and mechanical) of the used oil in diesel engine, which were sampled from a test engine with dynamometer and various cars. The properties of oil are TAN, viscosity, oxidation, ZDTP depletion factor and etc. Also the relation between the change of chemical and antiwear property of used oil was strongly related to ZDTP depletion factor as wall as the change of TAN(total acid number), sulfation and pentan unsoluble contents which were reated to the formation of protect film in sliding area. The oil used in pick-up(small) truck engine was deteriorated within the shortest distance than that of other cars. The antiwear property of used oil was decreased sharply as the running distance were over 5,000km. The oil used to mini bus was the least to deteriorate of properities for the funning distance.

• Journal of Energy Engineering
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• v.2 no.1
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• pp.68-74
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• 1993

In order to maximize the utility of vacuum residue, supercritical solvent extraction technique where n-pentane was used as a supercritical solvent was applied to obtain deasphalted oil from vacuum residue. Oil-extraction yield at various temperatures and pressures and the contents of metal complex and sulfur of extracted oil were investigated. In supercritical state, extraction yield of deasphalted oil was found to be strongly dependent on the n-pentane density, and the metal complex content of extracted oil was effectively lowered when compared with that of vacuum residue. However, the sulfur content of extracted oil showed little difference when compared with that of vacuum residue.

• Journal of the Korean Society of Food Science and Nutrition
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• v.21 no.6
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• pp.617-626
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• 1992

This study was designed to observe the effects of the feeding mixed oils of the sardine oil containing n-3 EPA(eicosapentaenoic acid) and DHA (docosahexaenoic acid) and the safflower oil in which were plenty of n-6 linoleic acid, on the fatty acid metabolism of serum and liver in the dietary hyperlipidemic rats. Experimental oils mixed with 16% butter(control group), 8% butter + 8% olive oil and 8% butter with various level of sardine and safflower oils were administered to the male rats of the Sprague Dawley for 4 weeks. In the fatty acid compositions of serum phospholipid, triglyceride and cholesteryl ester, according as the contents of mixed safflower oil increased, n-3 PUFA(polyunsaturated fatty acid) contents and ratio of EPA/AA(arachidonic acid) tended to be decreased, but n-6 PUFA contents and ratio of AA/PUFA tended to be increased. In the fatty acid composition of triglyceride component in liver lipid, DHA contents were most in the liver lipid. And components of cholesteryl ester, n-6 linoleic acid contents were high percentage. Fatty acid compositions of serum and liver lipids were influenced from the fatty acid composition of the test lipids.