• Korean Journal of Food Science and Technology
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• v.40 no.1
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• pp.15-20
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• 2008

This study investigated the antioxidant content and oxidative properties of roasted sesame oil during manufacturing and storage at $25^{\circ}C$ in the dark for 18 months. The manufacturing steps included pressing of the roasted sesame seeds, and then three filtering steps. Filtering decreased the oil viscosity, but increased free fatty acid content. The peroxide value (POV) was not affected by filtering. Sesamin, sesamolin, and tocopherol levels were significantly higher in the $3^{rd}$ filtered oil as compared to the other oils; however, sesamol content was reduced. The roasted sesame oil oxidized slowly during storage at $25^{\circ}C$ in the dark, and there was no POV change up to 9 months of storage. The levels of sesamol, sesamin, sesamolin, and tocopherols in the oil decreased with storage time, and the tocopherol decomposition rate (-3.04%/month) was higher than that of total lignan compounds (-1.06%/month). Therefore, these results suggest that tocopherols have priority over lignan compounds in performing as antioxidants in roasted sesame oil during storage.

• The Korean Journal of Food And Nutrition
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• v.27 no.1
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• pp.59-65
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• 2014

The fatty acid composition, selected minor components, and the oxidative stability of the mixed edible oil (perilla seed oil and rice bran oil, 3:7 (v/v)) were analyzed. The fatty acid composition of the mixed oil was 32.1% of oleic acid, 30.6% of linoleic acid, 21.4% of linolenic acid, 13.0% of palmitic acid, and 1.7% of stearic acid. The mixed oil contained ${\alpha}$, ${\gamma}$ and ${\delta}$-tocopherols and tocotrienols showing the highest contents of ${\alpha}$-tocopherol. Total amount of tocopherols contained in the mixed oil was 46.63 mg/100 g oil. The composition and content of phytosterols were determined by a GC equipped with a flame ionization detector. Total quantity of phytosterols in the mixed oil was 712.80 mg/100 g oil. The most predominant phytosterol in the mixed oil was ${\beta}$-sitosterol, followed by campesterol and stigmasterol, in a decreasing order. The oxidative stability of the mixed oil was much higher than that of perilla oil, and similar to that of soybean oil, indicating the high oxidative stability of the mixed oil.

• Journal of agriculture & life science
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• v.45 no.4
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• pp.121-133
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• 2011

Effects of roasting on vitamin E content, color, microstructure and moisture of peanuts, and vitamin E content in peanut oils prepared from the roasted peanuts were investigated. Runner-type peanuts were roasted at 140, 150, and $160^{\circ}C$ for 10-20 min. As roasting temperature and time increased, the CIELAB $L^*$ value of peanuts decreased while $a^*$ and $b^*$ values increased, resulting in formation of the golden brown color of roasted peanuts. Moisture ratio (M/Mo) and color $b^*$ value of peanuts roasted at 140 to $160^{\circ}C$ showed a correlation of $b^*=21.61\;(M/Mo)^2-40.62\;(M/Mo)+34.12$ ($R^2=0.9123$). Overall changes in the tocopherol contents of peanuts and peanut oils were significantly affected by roasting temperature and time (p<0.05). Roasting at $140^{\circ}C$ caused a slight increase in the levels of tocopherols of peanuts over roasting time up to 20 min (p<0.05). There was no significant change in the tocopherol levels of peanuts during roasting at $150^{\circ}C$ for 20 min (p>0.05). At $160^{\circ}C$, the levels of tocopherols significantly decreased during the initial 10 min of roasting (p<0.05) while there was no extended loss after 10 min, resulting in about 5, 12, 20, and 10% losses of ${\alpha}$-, ${\beta}$-, ${\gamma}$- and ${\delta}$-T, respectively. After 20 min, total tocopherols decreased by 18%. However, tocopherol contents of pressed peanut oils significantly decreased at all roasting temperatures (p<0.05). After roasting peanuts at $160^{\circ}C$ for 20 min, about 84% of initial ${\alpha}$-T in peanut oils was retained. ${\alpha}$-T was the most stable to roasting while ${\gamma}$-T was the least. Swollen epidermal cells on the inner surface and broken cell walls of parenchyma tissue of peanut cotyledon were observed in peanuts after roasting at $160^{\circ}C$ for 15 min. Severe changes in microstructure of peanut by roasting would contribute to vitamin E stability because of exposure of oil droplets in peanuts to oxygen.

• Proceedings of the Korean Society of Crop Science Conference
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• 2004.04a
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• pp.122-123
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• 2004

• 한국약용작물학회:학술대회논문집
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• 2012.05a
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• pp.311-312
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• 2012

• Journal of the Korean Applied Science and Technology
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• v.4 no.1
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• pp.77-81
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• 1987

No difference was observed on autoxidative stability of triacylglycerols before and after randomyl interesterification. It indicate that randomization of the glyceride composition has no significant effect on the autoxidative stability. On the other hand, the autoxidation of randomyl interesterified vegetable oil was accelerated, caused mainly by decrease of tocopherols during the series of interesterification procedures.

• Korean Journal of Plant Resources
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• v.26 no.6
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• pp.663-672
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• 2013

To characterize the nutraceutical property of Italian millet (Setaria italica) and sorghum (Sorghum bicolor), ten Korean landraces of each crop were collected and their vitamin E (tocopherols and tocotrienols), squalene and phytosterols (campesterol, stigmasterol and ${\beta}$-sitosterol) contents as well as fatty acid composition in seeds were evaluated. Italian millet seeds exhibited 5 forms of vitamin E isomers: three (${\alpha}$-, ${\gamma}$- and ${\delta}$-) tocopherols and two (${\alpha}$- and ${\gamma}$-) tocotrienols, while sorghum seeds showed only three forms of vitamin E isomers: ${\alpha}$- and ${\gamma}$-tocopherol and ${\alpha}$-tocotrienol. In both crops, ${\gamma}$-tocopherol was the major constituent of vitamin E in terms of highest quantity. Total vitamin E content in Italian millet and sorghum landraces were 88.3 mg/kg and 44.3 mg/kg, respectively. Among three phytosterols (campesterol, stigmasterol and ${\beta}$-sitosterol) analyzed, ${\beta}$-sitosterol was the major form comprising about 85% and 65% in Italian millet and sorghum landraces, respectively. Total phytosterols content ranged from 443.0 to 568.5 mg/kg and 442.3 to 719.2 mg/kg in Italian millet and sorghum, respectively. Squalene, a precursor of phytosterols biosynthesis, ranged from 6.8 to 10.2 mg/kg in Italian millet and from 62.2 to 115.2 mg/kg in sorghum. Linoleic, oleic and palmitic acids were the major fatty acids in both of the crops and about 80% of the total fatty acids were unsaturated fatty acids. Among the tested landraces, M09 and S10 showed relatively higher proportion of phytonutrients, suggesting their potential as a gene source for further breeding program.

• Nutrition Research and Practice
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• v.6 no.1
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• pp.21-27
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• 2012

Pumpkins have considerable variation in nutrient contents depending on the cultivation environment, species, or part. In this study, the general chemical compositions and some bioactive components, such as tocopherols, carotenoids, and ${\beta}$-sitosterol, were analyzed in three major species of pumpkin ($Cucurbitaceae$ $pepo$, $C.$ $moschata$, and $C.$ $maxima$) grown in Korea and also in three parts (peel, flesh, and seed) of each pumpkin species. $C.$ $maxima$ had significantly more carbohydrate, protein, fat, and fiber than $C.$ pepo or $C.$ $moschata$ (P<0.05). The moisture content as well as the amino acid and arginine contents in all parts of the pumpkin was highest in $C.$ $pepo$. The major fatty acids in the seeds were palmitic, stearic, oleic, and linoleic acids. $C.$ $pepo$ and $C.$ $moschata$ seeds had significantly more ${\gamma}$-tocopherol than $C.$ $maxima$, whose seeds had the highest ${\beta}$-carotene content. $C.$ $pepo$ seeds had significantly more ${\beta}$-sitosterol than the others. Nutrient compositions differed considerably among the pumpkin species and parts. These results will be useful in updating the nutrient compositions of pumpkin in the Korean food composition database. Additional analyses of various pumpkins grown in different years and in different areas of Korea are needed.

• Korean Journal of Food Science and Technology
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• v.24 no.6
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• pp.535-540
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• 1992

The antioxidant activities of Epimedium koreanum N. methanol extract on the oxidation of fats and oils were studied by measuring peroxide values during storage at $75^{\circ}C$. The methanol extract showed high antioxidant activity on the oxidation of lard and corn oil, and the antioxidant effectiveness increased as the concentrations of the extract in lard increased. After heating the extract at $180^{\circ}C$ for 120 min, the heat-treated extract exhibited above 66% of the original antioxidant effectiveness on the oxidation of lard during storage at $75^{\circ}C$. Epimedium koreanum N. extract, however, accelerated the oxidation of soybean oil during storage under irradiation of ultraviolet light. The main antioxidant components in Epimedium koreanum N. extract seemed to be tocopherols and flavonoids. The contents of ${\alpha}$, ${\beta}$, ${\gamma}$ and ${\delta}-tocopherol$ in the extract were 21.61, 1.48, 5.50 and 3.75 mg%, respectively.

• Korean Journal of Poultry Science
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• v.26 no.4
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• pp.217-236
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• 1999

Among polyunsaturated fatty acids (PURAs) targeted for manipulation in animal tissues (poultry eggs and meat), omega-3 PUFAs(n-3 PUFAs) are discussed in this review. 3 or 5% dietary menhaden oil (MO) supplemented layer diets was reported to increase docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) contents in the egg. MO at 1.5% also increased the deposition of up to 180mg total omega-3 fatty acids / yolk. Utilization of 5% ground flax seed (FS) resulted in similar total omega-3 fatty acid (FA) deposition as 1.5% MO. However, the basic feed formulations used in the Canadian feed industry usually include 10 to 20% FS in the egg laying diets. Recently several studies reported that addition of tocopherols in layer diets increased the tocopherol content more in the egg than any other tissue. One of reports said that 3.5% dietary oil with added tocopherols resulted in increasing tocopherol deposition and FA composition of the egg and other tissues. In the poultry meat, redfish meal (RM;4, 8, 12, 15 and 30% of diet) or redfish oil (RO;2.1 or 4.2% of diet) added to the practical corn-wheat-soybean based diets resulted in an increase in omega-3 FA and docosapentaenoic acid (DPA) contents in broiler meat lipids. Linseed oil (LO;1.0, 2.5, and 5.0% of broiler diet) supplemented in broiler diets also resulted in omega-3 FA and the ratio of omega-6 being significantly higher in poultry meat lipid than MO. Concern about fish flavor resulted in research about fish oil (FO) supplementation in broiler diets. Without the use of antioxidants, no more than 1.5% FO should be fed to broilers due to unacceptable orders from the chicken carcasses. One recent research project found that over 50mg/kg of vitamin E was required for maintaining the stability of unsaturated lipids in the meat. In regards to 'fishy'or 'crabby'taint in the eggs and poultry meat, poultry products remained acceptable when dietary fish oils were stabilized with antioxidants.