• Food Science of Animal Resources
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• v.34 no.3
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• pp.316-324
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• 2014

Milk fat is an important food component, and plays a significant role in the economics, functional nutrition, and chemical properties of dairy products. Dairy products also contain nutritional resources and essential fatty acids (FAs). Because of the increasing demand for dairy products, milk fat is a common target in economic fraud. Specifically, milk fat is often replaced with cheaper or readily available vegetable oils or animal fats. In this study, a method for the discrimination of milk fat was developed, using FAs profiles, and triacylglycerols (TGs) profiles. A total of 11 samples were evaluated: four milk fats (MK), four vegetable oils (VG), two pork lards (PL), and one beef tallow (BT). Gas chromathgraphy analysis were performed, to monitor the FAs content and TGs composition in MK, VG, PL, and BT. The result showed that qualitative determination of the MK of samples adulterated with different vegetable oils and animal fats was possible by a visual comparision of FAs, using C14:0, C16:0, C18:1n9c, C18:0, and C18:2n6c, and of TGs, using C36, C38, C40, C50, C52, and C54 profiles. Overall, the objective of this study was to evaluate the potential of the use of FAs and TGs in the detection of adulterated milk fat, and accordingly characterize the samples by the adulterant oil source, and level of adulteration. Also, based on this preliminary investigation, the usefulness of this approach could be tested for other oils in the future.

• Korean Chemical Engineering Research
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• v.51 no.4
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• pp.487-492
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• 2013

Transesterifications of waste oils mixed with animal tallows and vegetable oil by ultrasonic energy were examined over various catalysts for biodiesel production. Reaction activities of the transesterification were evaluated to the ultrasonic energy and thermal energy. The physicochemical properties of feedstock and products were also investigated to the biodiesels produced from the oils in the reaction using ultrasonic energy. The highest fatty acid methyl ester (FAME) yield was obtained on the potassium hydroxide catalyst in the transesterification by ultrasonic irradiation. The effective reaction conditions by ultrasonic energy were 0.5 wt% catalyst loading and 6:1 molar ratio of methanol to the mixed oils. The reaction rate of the transesterification by ultrasonic energy was faster than that by thermal energy. The highest yields of FAME were obtained as 80% in 5 min and the reaction equilibrium reached at that time.

• Journal of the Korean Applied Science and Technology
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• v.4 no.1
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• pp.9-18
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• 1987

The effects of procedures for preparation of fatty acid methyl esters for gas chromatography were investigated. A quantitative comparison of four procedures for the preparation of the fatty acid methyl esters from Korean sesame seed lipids which can be representative of fatty acid ranges of Korean vegetable oils has been made. The procedures employed were $BF_3$-methanol, HCI-methanol, sodium methoxide-methanol, and tetramethylammonium hydroxide-methanol. Twelve fatty acids ranged from 14:0 to 24:0 were identified in the lipids from Korean white and black sesame seeds. All four procedures gave similar results for the fatty acids, 16:0, 18:0, 18:1, 18:2, and 18:3 present in the range of $1{\sim}44%$ but only in the HCI-methanol procedure, the fatty acids, 16:1, 20:0, 22:0, 24:0 present in the range of $0.02{\sim}1%$ showed the lowest values. When using tetramethylammonium hydroxide-methanol procedure for determination of total fatty acid composition from white and black sesame seed lipids, unsaponifiable matters including sesamol, sesamolin and sesamin present in the seed lipids are not removed from the resulting reaction mixture. Thus the transesterification mixture is used without further treatment for injection into the gas chromatography. However, the gas chromatographic analysis of the transesterification mixture showed that the unsaponifiable matters had no effect on the fatty acid composition of the seed lipids. From the results, it appears that the $BF_3$-methanol, sodium methoxide-methanol and tetramethylammonium hydroxide-methanol procedures can be used to prepare fatty acid methyl esters from Korean vegetable oils. Among the methods, the tetramethylammonium hydroxide-methanol procedure, which give total fatty acid composition, glyceride fatty acid composition and composition of free fatty acids present, appears to be a simple, convenient and quantitative procedure and applicable to samples containing broad ranges of fatty acids.

• Food Science of Animal Resources
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• v.35 no.1
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• pp.130-136
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• 2015

This study was conducted to evaluate the quality properties of emulsion-type pork sausages when pork fat is replaced with vegetable oil mixtures during processing. Pork sausages were processed under six treatment conditions: T1 (20% pork fat), T2 (10% pork fat + 2% grape seed oil + 4% olive oil + 4% canola oil), T3 (4% grape seed oil + 16% canola oil), T4 (4% grape seed oil + 4% olive oil + 12% canola oil), T5 (4% grape seed oil + 8% olive oil + 8% canola oil), and T6 (4% grape seed oil + 12% olive oil + 4% canola oil). Proximate analysis showed significant (p<0.05) differences in the moisture, protein, and fat content among the emulsion-type pork sausages. Furthermore, replacement with vegetable oil mixtures significantly decreased the ash content (p<0.05), increased water-holding capacity in emulsion-type pork sausages. Also, cholesterol content in T6 was significantly lower than T2 (p<0.05). In the texture profile analysis, hardness and chewiness of emulsion-type pork sausages were significantly (p<0.05) decreased by vegetable oil mixtures replacement. On the contrary, cohesiveness and springiness in the T4 group were similar to those of group T1. The unsaturated fatty acid content in emulsion-type pork sausages was increased by vegetable oil mixtures replacement. Replacement of pork fat with mixed vegetable oils had no negative effects on the quality properties of emulsion-type pork sausages, and due to its reduced saturated fatty acid composition, the product had the quality characteristics of the healthy meat products desired by consumers.

• Journal of the Korean Society of Food Science and Nutrition
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• v.9 no.1
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• pp.39-44
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• 1980

The effect of dietary vegetable oils on the growth and blood glucose level of rabbit was examed. This study was carried out to observe the nutritive effect of feeding vegetable oils for a period of weeks. The experimental diets were prepared on the basis of isocaloric and isonitrogenous diet. The Experimental animals were fed on 5 kinds of diets such as control (Basal), group A(Basal + sesame oil), group B(Basal + perilla oil), group C(Basal + soybean oil), and group D(Basal + rice bran on diets for 4 weeks. The results obtained are summarized as follows: 1. The gain in body weight of rabbit was higher for perilla oil fed group than any other group gained. 2. Liver weight of the control group, group A, group B, group C, and group D were 30.35 or 37.35 or, 37.25 or, 38.25 gr, 31.05 gr, and 39.54 gr, respectively. The reletionship between liver and body weight were 3.25, 3.99, 4.33, 4,15, and 4.57, respectively. It showed that to liver weight of group D which was fed rice bran oil was heavier than any other group showed. 3. The content of total protein and glucase level in serum of animal blood were 5.72 mg% 40.34 mg%, 5.65 mg%: 22.37 mg%, 5.95 mg%: 77.0 mg%. 5.62 mg%: 28.60 mg%, and 5.63 mg%: 34.10 mg%, respectively. As shown above, the group B was the most heaviest one. 4. It may be concluded from the above results that linolenic acid which was included in vegetable oils have an effect on interconversion among three caloric elements such as cabohydrate, protein, and fats.

• Tribology and Lubricants
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• v.38 no.2
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• pp.41-52
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• 2022

Mineral electrical insulating oil, which is widely used in transformers, exhibits excellent cooling performance and transformer efficiency. However, given that it is composed of petroleum-based components, it is weak in terms of biodegradability. This causes environmental problems in case of leakage and a low flash point, which is a factor that would cause great damage in the event of a fire in a substation. In this context, the use of eco-friendly electric insulating oil composed of bio-based vegetable oil and synthetic ester, which has excellent biodegradability and flame retardancy performance, has recently been expanded to the field of electric power, and various research and development (R&D) studies are in progress. According to different research results, vegetable oil and synthetic ester manufacturing technology, thermal stability, oxidation stability, property change, and quality control, which are characteristics of eco-friendly electrical insulating oils, are major factors affecting the maintenance of insulating oil properties. In addition, power companies have established and operated quality control standards according to the use of eco-friendly electrical insulating oil as they expand the exploitatoin of renewable energy in electricity production. In particular, deterioration and oxidation characteristics were jointly identified in R&D as an important influencing factor according to the content of saturated and unsaturated fatty acids present in vegetable oils and synthetic esters in power transformer applications.

• Analytical Science and Technology
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• v.15 no.3
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• pp.248-255
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• 2002

The contents of ${\alpha}$-, ${\beta}$-, ${\gamma}$-, and $\delta$-tocopherols in sesame oils were determined by high performance liquid chromatography with UV detection. ${\alpha}$-Tocopherol contents ranged from 10.28 to 19.79 mg/g oil, ${\beta}$-tocopherol contents from 8.22 to 20.10 mg/g. However, both ${\gamma}$- and $\delta$-tocopherol were less than 1.49 mg/g or not detected. ${\gamma}$-Tocopherol was not detected from both unroasted white and black sesame seed oils. Significantly higher level of tocopherol in sesame oil than other oils is an evidence of the reason why it is highly stable and prevents oxidation. The tocopherol composition for twenty sesame oils was classified by using principal component analysis.

• Journal of the Korean Applied Science and Technology
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• v.2 no.2
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• pp.39-46
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• 1985

The study was carried out to investigate interrelationships among the acid, peroxide, iodine, thiobarbituric acid values, and changes of fatty acid compositions of some vegetable oils added to soybean milk. A storage temperature of $100^{\circ}C$ was used for the oxidation of the oils, and to determine of variation of the chemical properties and changes of the fatty acid composition, all the samples were carried out in every 8 hours for 40 hours. The changes in fatty acid compositions of the vegetable oils were measured by high performance liquid chromatography. The results obtained were as follow; 1. The acid values of the fresh soybean, corn, and palm oils added to the soybean milk were 0.05, 0.12, and 0.06, whereas those of the oils stored for 40 hours were 0.08, 0.18, and 0.09, respectively. 2. The peroxide values of the fresh soybean, corn, and palm oils added to the soybean milk were 0.3, 1.0, and 0.3, whereas those of the oils stored for 40 hours were 1.1, 1.1, and 0.9, respectively. 3. The iodine values of the fresh soybean, corn, and palm oils added to the soybean milk were 132.7, 124.1, and 57.0, whereas those of the oils stored for 40 hours were 127.3 108.3, and 52.0, respectively. 4. The thiobarbituric acid values of fresh soybean, corn, and palm oils added to the soybean milk were 0.18, 0.05, and 0.02, whereas those of the oils stored for 40 hours were 0.25, 0.19, and 0.07, respectively. 5. The percent content of the major fatty acids of the soybean, corn, and palm oils freshly added to the soybean milk were 2.3%,2.5%,and 25.2%for palmitic acid, 3.2%,3.2%,and 4.8%for stearic acid, 39.7%, 40.7%, and 59.3% for oleic acid, 49.9%, 53.0%, and 10.5% for linoleic acid, and 4.7%, 0.4%, and 0.7% for linolenic acid, respectively. Those of the oils stored for 40 hours were 2.9%, 4,5%, and 36.7% for palmitic acid, 8.5%, 6.8%, and 7.0% for stearic acid, 37.8%, 38.8%, and 49.2% for oleic acid, 46.2%, 49.5%, and 5.8% for linoleic acid, and 4.2%, 0.1%, and 0.1% for linolenic acid, respectively. The fatty acid compositions changed significantly: the amounts of the unsaturated fatty acid decreased considerably. The rsults of the present study demonstrated greater stability of the palm oil as compared with the stability of soybean oil and corn oil added to the soybean milk.

• Journal of Nutrition and Health
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• v.8 no.2
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• pp.19-26
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• 1975

The role of fat is important from nutritional standpoint. The physiological functions of fat are energy yielding as well as the carrier of fat soluble vitamins, with special activities of essential fatty acids. It is fortunate that Korean families prefer to use vegetable oils rather than those from animal origin. But the problems are focused on better qaulity of food oils with attempt to exploit the available resources. This study was undertaken to inevestigate the fatty acid compositions of Korean origin both from conventional and unconventional resources of gas-liquid chromatography. The results obtained are as follows. 1. The total lipid contents of seeds of red pepper, Korean squash, sesame, perilla (var Japonica), and Korean pine nuts and walnuts were 24.3%, 56.6%, 56.4%, 46.9%, 69.8%, and 67.2%, respectively. 2. The saponification numbers of samples ranged from 190 to 200. It showed that the mean molecular weights of fatty acids composing the lipids were very much closed each other. 3. Iodine numbers of varing seed oils ranged from 96.5 of Korean squash seed oil to 124.6 of walnut oil. Oils obtained from squash seeds and sesame seeds showed significantly lower value, while others ranged from 122 to 125. 4. In the fatty acid compositions, squash seed oil was composed mainly of unsaturated fatty acids, 74.9% of which was oleic acid, whereas red pepper seed oil, pine nut oil, and sesame oil contained linoleic acid as a major component showing 64.4%, 56%, 48.8%, and 47.8%, respectively. In perilla seed oil, the amounts of linoleic and linolenic acids were 14.1% and 58%, respectively which meant nearly three-fourths of the total fatty acidsbeing the unsaturated essential fatty acids. This study will encourage the use of these conventional and unconventional vegetable oils which have highr ratios of polyunsaturated to saturated fatty acids.

• Microbiology and Biotechnology Letters
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• v.20 no.4
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• pp.477-482
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• 1992

A bacterial strain Acinetobacter calcoaceticus was examined for its ability to degrade fats, oils and hydrocarbons, and tested for the possibility of application in wastewater treatment. All fats and oils tested were degraded by the strain. About 60% of hexadecane, 26% of fish oiL and 40-54% of vegetable oils were consumed respectively in shaking-flask culture. Saturated fatty acid compositions were about 55% in fish oil and 6-12% in vegetable oils. Increases in cell mass were accompanied with decreases in the concentrations of carbon sources. When jar fermentor in place of shaking-flask was used as a culturing vessel. above 80% of all carbon sources was consumed and yield of cell mass was improved to nearly 1.00. Synthetic wastewaters containing 3% of fat, oil, or hydrocarbon as a sale ca,bon source were treated sequentially with A. calcoaceticus first and then exposed to activated sludge. The concentrations of carbon sources were decreased below 0.06% through the process, and the concentrations of suspended solids were lower than 53 mglml. The data imply the potential use of A. calcoaceticus in wastewater treatment.