• Preventive Nutrition and Food Science
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• v.14 no.3
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• pp.260-264
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• 2009

A high-performance liquid chromatography method was applied to determine the contents of tocopherols in edible oils using a LiChrosorb DIOL HPLC column and hexane fortified with 0.1% acetic acid in an isocratic mode. The validation of the method included tests for linearity, sensitivity, accuracy, precision, and recovery. All calibration curves showed good linear regression ($r^2$>0.9995) within the tested ranges. The established method offered good precision and accuracy with overall intra-day and inter-day variations of 0.94$\sim$4.27 and 1.77$\sim$ 4.88%, respectively. The tocopherol recoveries ranged from 91.44$\sim$108.90%. Subsequently, the method was successfully applied to qualitatively and quantitatively determine the total contents of $\alpha$, $\gamma$, and $\delta$-tocopherols in 12 selected refined edible oils, showing a range of 0.92 to 188.71 mg/100 g.

• Food Science and Industry
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• v.50 no.4
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• pp.65-81
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• 2017

In Korea, sesame oil has been used as a flavor source mainly by edible oil since ancient times, and it has been used by domestic screw pressing. In the 1960's, the demand for edible oils and fats increased significantly due to the improvement of national income and changes in food consumption patterns. In the early 1970's, a few edible oil manufacturing companies with modern solvent extraction and refining plants were established. In Korea, edible oil manufacturers account for more than 85% of employees with 50 or fewer employees. In Korea, there is a very shortage of raw materials for edible oils and fats, domestic production of edible oil is decreasing year by year and import volume is continuously increasing. While importing the edible oil bearing ingredients including soybean and extracted oil in the past, recently mainly imports crude oil and refines it in Korea. Soybean oil, palm oil and tallow account for 70~90% of total imported edible oils. Due to the recent well-being trend, the demand for olive, canola and grapeseed oils as household edible oil has increased and the production of blended oil has been greatly increased. Since the late 1980's, people have recognized edible oil and fat as a food instead of seasoning ingredient and have increased their edible oil and fat intake in Korea. Since the early 2000's, refined oil and fat products produced in Korea have been exported and is increasing every year.

• Korean Journal of Food Science and Technology
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• v.39 no.2
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• pp.133-137
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• 2007

The 2,2-diphenyl picrylhydrazyl (DPPH) method, which can be used to predict the oxidative stability of edible oils, was previously reported by our research group. Not only free radical scavenging antioxidants but also radicals from oxidized oils are capable of reacting with DPPH radicals, thereby reducing the absorbance of DPPH. In this study, the optimum sample size of edible oils for the DPPH method was determined, and the oxidation of the edible oils was monitored via DPPH, coupled with other conventional methods. The optimum sample size was determined as 1.5 g using soybean oil. Soybean, corn, virgin olive, and refined olive oils were thermally oxidized for 3 hr at $180^{\circ}C$ and analyzed via DPPH, conjugated dienoic acid (CDA) value, and p-anisidine value (p-AV) protocols. Soybean and corn oils were found to be more sensitive to thermal oxidation than virgin and refined olive oils, on the basis of the CDA value and p-AV measurements. The DPPH method can indicate the inherent radical scavenging activity of unoxidized samples, the time required for the depletion of antioxidants, and the rate of degradation of the antioxidants. The soybean and corn oils evidenced higher levels of free radical scavenging compounds, required more time for the consumption of inherent antioxidants, and also manifested steeper antioxidant degradation rates than olive oils, based on the results of DPPH analysis. The DPPH method, accompanied by other conventional methods, may prove useful in predicting the degree of oxidation of vegetable oils.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.21 no.4
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• pp.232-238
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• 1988

As a part of the studies on effective utilization of polyunsaturated lipids in sardine (Sardinops melanosticta), when the refined sardine oil was mixed with soybean and other vegetable oils storage stability and the effect to the quality of the product was investigated. Addition of 1 volume of refined sardine oil to 4 volumes of soybean oil was recommended to yield 3 in P/S ratio and 1.5g of eicosapentaenoic and docosahexaenoic acid per 40g of the mixed oil for a good storage stability and as a dietary source of EPA requirement for atherosclerotic disease. When the unpurified vegetable oils, sesame oil and perilla oil, were mixed with the same volume of refined sardine oil the content of n-3 fatty acids was increased to $13.36\%\;and\;30.65\%\;%\;from\;0.27\%$ in sesame oil and $29.72\%$ in perilla oil. The n-3/n-6 ratios were also raised to 0.476 and 1.433 from 0.006 and 0.876. And these mixed oils were more stabilized than the refined sardine oil during storage at $30^{\circ}C$.

• Food Science and Industry
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• v.51 no.2
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• pp.114-126
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• 2018

The production of high quality oil to meet new standard needs a 'next generation' innovative oil refining tool in paradigm shift. 'Nanoneutralization' using controlled hydrodynamic cavitation-assisted Nanoreactor is successfully being introduced and commercialized into edible oil industry and it plays a key driver for sustainable development of food processing. This emerging technology using bubble dynamics as a consequence of Bernoulli's principle by hydrodynamic cavitation in Venturi-designed multi-flow through cell is radically changing the conventionally chemical-oriented neutralization. Nanoneutralization derived by the creation of nanometer-sized bubbles formed through scientifically structured geometric channels under high pressure has been proven to improve mass transfer and reaction rate so substantially reduce the chemicals required for refined vegetable oil and to increase oil yield while even improving oil quality. More researches on science behind this revolutionary technology will help usto better understand the principle and process hence makes its potential applications expandable in extraction, refining and modification of fats and oils processing.

• Food Engineering Progress
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• v.13 no.3
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• pp.211-215
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• 2009

Concentrations of benzo[$\alpha$]pyrene in edible oils from Korean market were evaluated by high performance liquid chromatography. Benzo[$\alpha$]pyrene known of the carcinogenic polycyclic aromatic hydrocarbons(PAHs), has been found at variable concentrations in several foods. This is associated with several factors during the process including contaminated raw materials, exposure of environment, and procedure of process or cooking. The levels of benzo[$\alpha$]pyrene were ranged from 0.5 to 1.4 $\mu$g/kg in virgin olive oil. Benzo[$\alpha$]pyrene contents in refined and virgin olive oil, sesame oil, soybean oil, corn oil, sunflower oil, safflower oil, and processed oil were 0.6-1.0 $\mu$g/kg, 0.9-1.3 $\mu$g/kg, 0.6-3.3 $\mu$g/kg, 0.5-1.1 $\mu$g/kg, 1.2-1.7 $\mu$g/kg, 1.0-2.1 $\mu$g/kg, and 1.0-1.4 $\mu$g/kg, respectively.