• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.35 no.1
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• pp.19-26
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• 2003

In recent years, numerous studies have been carried out to find out the possible substitution of PE-coated paperboards used in packaging of watery or oily foods. Accordingly, this study was carried out to obtain the basic data for producing higher functional coating agents for pulp mold by evaluating various kinds of mixed coating agents. At that time, two kinds of synthetic coating agents(AKD, PYA) and three kinds of natural coating agent(CMC, corn starch, oxidized starch) were used for making the mixed coating agents respectively. Physical properties of coated paperboards were tested. Conclusions obtained from this study were as follows. Based on concentrations, the proper mixture ratios were 10:90(AKD:CMC), 10:90(AKD:corn starch), 10:90(AKD:oxidized starch), 40:60(PVA:CMC), 20:80(PVA:corn starch) and 20:80(PYA:oxidized starch). The mixed coating agent of PYA:corn starch(20:80) was the most efficient coating agent. Consequently, water and oil resistance were improved even with much addition of natural coating agents. We consider that they can be suitable for the packaging used in the storage of higher moisture vegetables and other food, and also can be suitable for oily fried food.

• Korean journal of food and cookery science
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• v.5 no.2
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• pp.51-62
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• 1989

In the present study, an attempt was made to investigate the oxidative stability of the various sesasme blended oils. Sesame blended oils were perpared by mixing sesame oil with various vegetalbe oils (soybean oil, corn oil, ricebran oil, rapeseed oil, cottonseed oil, and perilla oil) in a ratio of 3:7 (w/w). Fatty acid composition and some of physico-chemical characteristics of the sesame blended oils and vegetable oils including sesame oil were determined before the oxidation experiments. The fatty acid compositions and the physico-chemical characteristics of the vegetable oils changed by blending the oils with sesame oil and the extent of change varied with the type of oil. Particularly, the iodine value of the vegetable oils decreased significantly by sesame oil blending. The sesame blended oils and the vegetable oils including sesame oil were oxidized at $45^{\circ}C$ for 25 days in a dark place, and at $35^{\circ}C$ for 12 days under the irradiation of incandescent electric lamp (40 W). During the oxidation, some physico-chemical characteristics of the oils were determined to evaluate the oxidative stability. Based on the changes of peroxide values, the oxidative stability of the vegetable oils was improved by sesame oil blending.

• Journal of Nutrition and Health
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• v.17 no.2
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• pp.113-125
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• 1984

The long-term effects of vegetable and animal high fat diet on the lipid metabolism were investigated in male weaning rats. The rats were fed one of four semipurified diet ad libitum : control diet supplied 12% of calories as fat(control group), low fat diet supplied 3% of calories as fat(3% F group), 45% corn oil diet supplied 45% calories from corn oil(45% C group) and 45% butter fat diet supplied 45% calories from butte. fat(45% B group). The weights of liver, content of triacylglycerol(TG), total cholesterol and phospholipid(PL) in liver were investigated. The weight of liver of rats, fed 45% corn oil at 12 weeks and fed 45% butter fat for all period of diet were higher than that of control group. The contents of TG in liver of rats, fed 45% corn oil from 8 weeks and fed 45% butter fat for all period of diet were higher than that of control group. The levels of TG in liver of rats fed 45% butter fat were higher than those of rats fed 45% corn oil. The contents of total lipid and cholesterol in liver of rats were increased with similar trend of TG level, but contents of PL in liver had no relation with the levels and types of dietary fat and feeding periods. The liver of rats were observed histochemically by light microscope. Mild to severe level of fatty changes in liver of 45% C and 45% B group were observed at 8 and 12 weeks of diet. The liver of rats in control group appeared to be healthy and normal electron-microscopically, but in fatty degenerated hepatocytes of 45% C and 45% B group, nuclear membranes were irregular and a great number of intracytoplasmic fat vacuoles in cells were variable in size and low in electon density. The numbers of lysosome were increased and secondary lysosomes among them were observed on electron microscope.

• Journal of Nutrition and Health
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• v.25 no.7
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• pp.555-568
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• 1992

This study was to compare the effects of dietary n-6 and n-3 fatty acids and fat unsaturation on plasma lipids and chemical composition of VLDL and LDL fraction and lipogenic enzymes activity in rat liver under the conditions providing 1) a similar amount of n-6, n-3 fatty acids(LA, ALA, EPA+DHA) in diets and 2) the various degree of fat unsaturation. Male Sprague-Dawley rats weighing 420g were treated for 6-n with six experimental diets providing 25% of energy as fat and which were different only in fatty acid composition. The fats used for a source of each fatty acid were beet tallow for saturated fatty acid corn oil for n-6 linoleic acid(LA) perilla oil for n-3 $\alpha$-linolenic acid(ALA) and fish oil n-3 eicosapentaenoic acid (EPA) and n-3 docosahexaenoic acid(DHA). Plasma cholesterol level was increased by corn oil to compare with beef tallow but was decreased by perilla oil or fish oil. Plasma TG level was significantly decreased by perilla oil or fish oil. Fish oil significantly reduced the level of HDL-Chol and the proportion of Chol in LDL fraction and that of TG in vVLDL fraction. Overall there was a singificant negative correlation between the level of each plasma lipid(Chol TG, VLDL-TG, LDL-C) and the degree of fat unsaturation. However this rerlationship is not always true when compared the hypolipidemic effect of each fatty acid at a similar level of fat unsaturation. There was a trend such taht glucose 6-P dehydrogenase 6-phosphogluconate dehydrogenase and malic enzyme activites were reduced by n-3 fatty acids. Perilla oil significantly increased the incorporation of c20:5 and c22:5 into liver tissue and fish oil suignificantly increased the incorporation of c20:5, c22:6 into liver tissue and the effect of long chain n-3 fatty acid incorporation was greater by fish oil. therefore the hypotriglyceridemic effect of n-3 fatty acid could be resulted from the interference of hepatic lipogenesis by long-chain n-3 fatty acids and the reduced proportion of TG in VLDL fraction and its effect was greater by n-3 EPA+DHA than n-3 ALA even though plasma Chol and TG levels were also influenced by the degree of dietary fat unsaturation.

• Journal of Food Hygiene and Safety
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• v.22 no.4
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• pp.311-316
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• 2007

Trans fatty acid components separated and quantified using a SP-2560 capillary column in a gas chromatograph (GC) with flame ionization detector (FID). Trans fatty acid and total fatty acid contents were measured in 21 corn oils. Ranges of values for trans fatty acid (tFAs) contents of total fat (as g/100g fatty acids) were com oils $0.65{\pm}0.31$. Corn oils were heated at $175{\pm}5^{\circ}C$ for 5mins $(0{\sim}15\;times)$. The contents of tFAs (g/100) were increased from 0.292 (0 time) to 2.585 (15 times) in com oil. When frying oils (15 times) were incubated at $20{\pm}5^{\circ}C$ for 150 days, the contents of tFAs (g/100g) were increased from 2.585 to 3.683 in com oil. The amounts of tFAs (g) per serving size of frying oils (15 times) were increased from 0.01 to 0.18 in corn oil. The levels of the 18:1 trans isomers increased significantly the time of reusing of com oil.

• Korean Journal of Food Science and Technology
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• v.35 no.5
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• pp.797-802
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• 2003

Structured lipids (SL) were synthesized by esterification of corn oil and conjugated linoleic acid (CLA) in a continuous packed-bed column reactor. The effects of flow rate, reaction temperature, and substrate molar ratios were studied. The reaction was catalyzed by TL IM (immobilized lipase from Thermomyces lanuginosa). Results of triacylglycerol (TAG) analysis by GC showed that the incorporated CLA isomers were mainly cis9, trans11- and trans 10, cis12-CLA. Slower flow rates yielded higher incorporation, and maximum incorporation of CLA was obtained with a molar ratio of 1:3 (corn oil: CLA) at a temperature of $55^{\circ}C$. The obtained SLs had iodine values ranging from 120 to 128. The SLs were composed of TAG $(98{\sim}99%)$, 1,2- and 1,3-diacylglycerol ($0.7{\sim}1.3%$), and a small amount of monoacylglycerol.

• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.6
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• pp.1000-1005
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• 2004

Structured lipids (SLs) were synthesized by acidolysis of crude oils (corn and peanut oil) and conjugated linoleic acid (CLA) with a molar ratio of 1:3 (extracted oil:CLA) in a shaking water bath. The reaction was performed for various reaction time (1, 2, 3, 6 and 24 hr) at 55$^{\circ}C$ with 175 rpm catalyzed by sn -1,3 specific IM 60 lipase from Rhizomucor miehei. The content of the incorporated CLA increased with the prolonged reaction time, showing 7.5∼9.3 ㏖% in the synthesized SL triacylglycerol molecules from the extracted corn and peanut oil. However, total tocopherol content in SLs decreased up to about 20% compared to the content in extracted oils. Among the CLA isomers, 6.3∼7.5 ㏖% of cis 9,trans 11- and trans 10,cis 12-CLA known as physiologically active compounds are contained in corn and peanut SLs.

• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.10
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• pp.1513-1517
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• 2016

Rice bran contains high amounts of fiber and various phytochemicals, including vitamin E, ${\gamma}$-oryzanol, and phenolic acids. The oxidative stabilities of corn oil added with three rice bran extracts from two rice cultivars (Dasan 1 and Ilpum) were evaluated. The three rice bran extracts were unsaponifiable matter of rice bran (USM), methanolic extract of rice bran oil (MEO), and methanolic extract of defatted rice bran (MEDR). Each sample was stored at $50^{\circ}C$ for 24 days. Oxidation of these samples was determined every 3 days by measuring the peroxide value (POV) and conjugated diene value (CDV). Vitamin E content was analyzed on day 0 and day 24. The results show that the POV and CDV values of samples increased gradually during the storage period. The order of oxidative stability was shown as BHT> MEDR> MEO> USM> control, regardless of cultivars. In the case of vitamin E, ${\alpha}$-T, ${\gamma}$-T, ${\alpha}$-T3, and ${\gamma}$-T3 contents decreased by 89%, 31%, 83%, and 32% after storage for 24 days, respectively. In conclusion, MEDR showed higher oxidative stability and may have potential as a source of natural antioxidants in the oil industry.

• Journal of Life Science
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• v.32 no.5
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• pp.362-367
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• 2022

Hempseed, a dehulled Cannabis fructus, has high nutraceutical potential. It has plenty of essential amino acids, vitamins, and essential polyunsaturated fatty acids, including α- and γ-linolenic acid. Increased exercise capacity, cognitive function, and ameliorative effects against hypercholesterolemia, neuro-inflammation, thrombus formation, and learning and memory impairment were reported in hemp-seed oil-administered models. Therefore, the market prices of hempseed oil are 45~140-fold higher than the other plant-derived oils, such as soy, corn, olive, canola, or linseed oil. In this study, instead of FTIR (Fourier Transform Infrared Spectroscopy) or FTIR-Raman spectroscopy, a simple UV-Vis spectrophotometry method was developed to authenticate the hempseed oil. Measurements of absorbance at 245, 305, and 415 nm of oils and calculations of 245/415 and 315/415 nm provided that the ratios of 245/415 and 315/415 nm of authentic hempseed oils were 12.9 and 9.6, respectively. The 245/415 and 315/415 nm of soy oil, corn oil, canola oil, and linseed oil were 35.4~61.8 and 29.7~50.8, respectively. This simple UV-Vis spectrophotometry method could also be applied to differentiate hempseed oil from blended oil products in markets.

• Preventive Nutrition and Food Science
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• v.6 no.3
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• pp.170-175
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• 2001

This study was designed to investigate the effect of different sources of $\omega$3 fatty acid in the diet with a similar polyunsaturated/saturated (P/S) fatty acid ratio and $\omega$6/$\omega$3 fatty acid ratio as well as excess DHA on the plasma fatty acid composition and cholesterol level of rats. Three experimental diets contained 10% (w/w) dietary lipids. The control diet and one treatment diet were corn oil-based diets with different $\omega$-3 fatty acid sources: perilla (CO) or fish oil (CF), respectively. In order to examine the effect of excess DHA, the other treatment diet (FO) was a fish oil-based diet with corn oil to supply essential fatty acids at the level of 1.8% (w/w) of the diet. Female Sprague Dawley rats were fed the experimental diets for 2 weeks prior to mating and throughout gestation and lactation. Pups were weaned to the same diet of dams at 21 days of age. Plasma fatty acid compositions and cholesterol contents were analyzed for pups at 3th, 7th and 10th week after birth. Plasma DHA concentrations increased significantly as the level of fish oil supplementation increased. Three-, seven- and ten-week old rats fed on CO diet which contained only $\alpha$-lino1enic acid as a $\omega$-3 fatty acid Source had Plasma DHA levels of 4.85%, 3.15% ana 2.47%, respectively, suggesting that rats at this period of development can convert $\alpha$-linolenic acid to DHA. But the ability to form DHA might be limited, since dietary DHA showed to be more effective in raising the plasma level of DHA. There was a significant negative correlation between DHA and cholesterol concentration of the rat plasma at 7th week (r=0.34, p<0.05) and l0th week after birth (r=036, p<0.05), proving the hypocholesterolemic effect of DHA.