• Analytical Science and Technology
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• v.15 no.4
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• pp.388-391
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• 2002

Rancidity of a soybean oil is investigated by an electrochmical method. The redox process of the soybean oil is totally irreversible and diffusion-controlled reaction. As scan rates are faster, the anodic peak potential of the soybean oil is shifted to the positive potential and the anodic current is increased. The anodic peak potentials of the soybean oil is not rarely changed up to open-42 days in the both atmosphere and room temperature. After the open times, the anodic peak potential is largely shifted to a negative direction. This indicates the oxidation of the soybean oil becomes easier. The anodic peak current of the soybean oil is decreased gradually up to open-42 days. But after the open times, the anodic peak current increases suddenly. It must be due to the formation of a carbonyl group owing to rancidity of the soybean oil.

• Korean journal of food and cookery science
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• v.19 no.1
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• pp.60-64
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• 2003

Yukwa is a popular Korean traditional fried rice snack. The high fat content and porous structure of Yukwa cause it to become rancid rapidly. For extending the shelf-life of Yukwa, the Bandegi was fried with palm oil and soybean oil. The stability of Yukwa in lipid oxidation was determined by acid value(AV), peroxide value(POV), composition of fatty acid and sensory evaluation during 8 weeks of storage at 20$^{\circ}C$ and 50$^{\circ}C$ As the storage time increased, the AVs of soybean oil and palm oil during storage at 50$^{\circ}C$ were increased up to 42.64 and 2.09 mg/g, respectively. The POV of soybean oil during storage at 50$^{\circ}C$ was increased up to 4 weeks and then decreased. And as the storage time increased, the contents of stearic and oleic acid were increased, while linoleic and linolenic acid were decreased.

• Korean Journal of Food Science and Technology
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• v.10 no.2
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• pp.112-118
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• 1978

Four domestic frying oils (soybean, corn, rapeseed and rice bran oil) were studied on their changing properties according to thermal oxidation by means of chemical analysis of their compositions and measurements of various physical and chemical properties. The content of linoleic acid which is an essential unsaturated fatty acid and the total amount of unsaturated fatty acids were highest in soybean oil (53.2% and 80.3% respectively) among the unheated frying oils and the degree of its thermal degradation was lowest during the continuous heating period for 48 hours at $180^{\circ}C$. However in general, the contents of unsaturated fatty acids were sharply decreased by thermal oxidation whereas the saturated fatty acid contents ranging 10-17% were not changed considerably, which largely agreed with the results of iodine value measurements. The free acid and peroxide values were also lowest in soybean oil (0.09 and 5.6 respectively) among the unheated oils whereas an anomalously high free acid value was observed in rapeseed oil (54.8) which was packed in unleveled glass bottles. Such a high value is probably ascribed to the photo-catalyzed oxidation during storage. The viscosity measurements have shown similar values before heating, but after thermal oxidation for 32 hours the rapeseed and rice bran oils became too thick to measure viscosity by capillary flow method with heavy darkening in color.

• 프린팅코리아
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• v.7 no.10
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• pp.74-76
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• 2008

대형 유통업체들이 잇따라 '환경가치 경영'을 발표하며, 콩기름을 사용한 전단을 발행하는 등 환경경영에 적극 나서고 있다. 2004년 '환경경영'을 선포한 롯데백화점은 광고전단을 '콩기름잉크'를 사용하고 있다. 신세계 이마트도 점내 안내문을 '재생용지'로 변경, 사용해 오고 있으며, 이 양만해도 연간 약 300 톤에 달한다. 이들 대형 업체들은 인쇄업체도 친환경기기 및 기자재를 사용해야 한다고 밝히고 있어, 바야흐로 인쇄의 친환경 시대가 도래하고 있음을 보여주고 있다.

• Journal of the Korean Society of Food Culture
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• v.18 no.2
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• pp.89-95
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• 2003

In order to evaluate the oxidative stability and sensory evaluation for the pine needle extracted oils, we prepared the pine needle extracted oils by the autoclave method with soybean and/or olive oils. The lipid peroxidation was monitored by measuring the formation of 2-thiobarbituric acid reactive substances(TBARS). In addition, the secondary reaction products of lipid oxidation were measured by fluorescence spectroscopy. A weight changing was decreased in oils added pine needle during storage periods. The formation of TBARS was the lowest in olive pine needle oils after 14 days storage, whereas it was the highest in soybean oil. The levels of fluorescent products in extracted oils added pine needle were also decreased in organic layers. According to the sensory evaluation, the scores of fragrance, taste and overall preference in savored laver using an pine needle extracted oils were no significant differences. Overall results suggest that the pine needle extracted oils can be developed to functional oil resources.

• Korean Journal of Food Science and Technology
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• v.50 no.6
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• pp.565-571
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• 2018

After adding eight different kinds of PAHs to soybean oil and perilla oil samples, changes of PAHs contents after activated carbon treatment with different conditions of activated carbon concentration, temperature, and time were investigated. PAHs contents decreased in both soybean oil and perilla oil with increasing activated carbon concentrations. Neither of the PAHs were detected in the soybean oil samples after the addition of only 0.05% of activated carbon, while the contents of most kinds of PAHs decreased below the limit of quantification in the perilla oil samples after the addition of up to 0.4% of activated carbon. PAHs contents decreased as the temperature of the activated carbon treatment increased, and most PAHs were not detected in the soybean oil samples at temperatures above $80^{\circ}C$. With regards to the activated carbon treatment time, the PAHs contents also decreased as the treatment time increased. In case of soybean oil, four kinds of PAHs were not detected after treatment with 0.05% of activated carbon at $70^{\circ}C$ for 10 min.

• Journal of Nutrition and Health
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• v.19 no.3
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• pp.135-145
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• 1986

식이 $\omega$3 지방산이 신장의 지질구성 및 기능에 미치는 영향을 조사하기 위해 젖뗀 55-60 g의 흰쥐에게 고등어유, 들깨유, 콩기름을식이의 10% (W/W)포함하는 먹이를 조제하여 24일간 섭취시켰다. 고등어유군의 신장 인지질 지방산에 C20~C22 $\omega$ 3 지방산의 함량이 월등히 많은 반면 들깨유군은 콩기름군에 비해 약간 높을 뿐이어서 C18 : 3 ($\omega$3) 지방산으로 단기간에 쉽게 전환되지 않음을 보였다. C18 : 2($\omega$6) 지방산은 고등어군만 낮았고 C20 : 4($\omega$6)는 들깨유군에서는 낮았지만 고등어유군은 콩기름군과 같은 수준이었다. 또한 고등어유군에서 C18 : 1($\omega$9)을 포함한 단일 불포화 지방산이 높고 포화지방산 함량이 낮은 것도 특징이었다 . 인지질 종류별 분석결과에서 고등어유군이 sphingomyelin 이 높고 phosphatidylethanol-amine이 낮았다. 반면 신장 Cholest대기 함량은 고등어유군이 높았으며, 이러한 지질구성 변화는 신장 Na-K-ATPase 활성감소시킨 것이다.

• International Journal of Highway Engineering
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• v.9 no.2 s.32
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• pp.13-25
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• 2007

Viscosity, adhesion and cohesion of asphalt binder are very important characteristics in asphalt pavement. However, these characteristics can cause some problems such as inaccurate amount of asphalt mixture, reduction of asphalt content and loss of workability during asphalt pavement construction. Asphalt release agent has been used to solve these problems. Diesel oil and vegetable oil are generally used as an asphalt release agent in Korea. However, these agents have been criticized from environmental and binder integrity reasons. Therefore, this study evaluated the characteristics of asphalt release agents including diesel oil, vegetable oil and two emulsion type oils. From the study, it was found that the diesel oil resolved the binder within ten minutes and vegetable oil stripped the binder from mixture within one hour after contacting with asphalt mixture. And also, from the test for estimating the application cycle of asphalt release agent, it appears that diesel oil and vegetable oil should be applied to construction equipments every time in their uses. However, diesel oil and vegetable oil showed a good performance as a lubricant for detaching the asphalt mixtures from the truck bed.

• The Korean Journal of Pesticide Science
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• v.13 no.4
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• pp.203-208
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• 2009

In order to elucidate the effect of spreader-stickers on the rainfastness of dithianon and chlorothalonil wettable powders, and to estimate the possibility of suggesting good new formulations, the fungicide residues on the leaf surface of hot pepper was assessed and compared after the drop-wise applications of fungicide suspensions containing spreader-sticker on leaf surface followed by artificial raining. Three commercial spreader-stickers, which were Cover, Reitron and Silwet, not only made the rainfastness of dithianon wettable powders worse on hot pepper leaf, but increasing their concentrations also accelerated it further. On the other hand, to chlorothalonil wettable powder, Reitron showed the 3-fold improvement of rainfastness. But, for the rest, there was no improvement as well. The effect of N-octylpyrrolidone (NOP) on rainfastness of both fungicides was excellent. Soybean oil formulations containing leaf-penetrable nonionic surfactant, which was either polyoxyethylene monotridecyl ether or polyoxyethylene monolauryl ether, improved dithianon rainfastness, but the ones containing conventional emulsifiers did not.

• Korean Journal of Food Science and Technology
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• v.17 no.3
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• pp.141-145
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• 1985

In the present study, an attempt was made to investigate the characteristics of rheological properties of a themally oxidized soybean oil. Various flow curves of the oxidized oils were obtained using a broad range of shear rate (452-904 rpm). The flow curves showed the characteristics of thixotropic flow, and as temperature decreased (range : 13-$37^{\circ}C$) they demonstrated increasingly stronger thixotropic properties. A thixotropic slope similar to the coefficient of thixotropy as applied to the rheological characteristics of the thermally oxidized soybean oil to predict its rheological properties quantitatively at an equilibrium state. The empirical formula with the thixotropic slope was found satisfactory in predicting the Non-Newtonian behavior of the thermally oxidized soybean oil.