• Korean Journal of Food Science and Technology
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• v.25 no.4
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• pp.307-312
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• 1993

Antioxdant effect was studied in model system with linoleic acid methylester and tocochromanols $({\alpha}-,\;{\beta}-,\;{\gamma}-,\;{\delta}-tocopherol\;and \;{\alpha}-,\;{\gamma}-,\;{\delta}-tocotrienol)$ under definite autoxidation condition-temperature $(40,\;60,\;80^{\circ}C),\;O_2\;(0,\;10,\;20%\;O_2\;in\;N_2)$. 13-Hydroperoxy-9-cis-11-trans-, 13-hydroperoxy-9-trans-11-trans-, 9-hydroperoxy-10-trans-12-cis-, 9-hydroperoxy-10-trans-12-trans-octadecadienoic acid methylester as the major oxidation product were produced from linoleic acid methylester by autoxidation, analyzed with HPLC and antioxidant activities were compared by their quantitative changes. Experimental results showed that all added tocochromanols except ${\alpha}-tocotrienol$ had antioxidant effect at $60^{\circ}C$, and also ${\alpha}-tocopherol$, ${\alpha}-tocotrienol$ and ${\delta}-tocotrienol$ had prooxidant effect at $80^{\circ}C$. And cis/trans-hydroperoxide was predominantly produced at $40^{\circ}C$, but trans/trans-hydroperoxide at $80^{\circ}C$. Except no reproductive experimental data in produced hydroperoxides amount, the production ratio of cis/trans-:trans/trans-hydroperoxides in the autoxidation condition of range from $40^{\circ}C/10%,\;O_2\;to\;60^{\circ}C/20%\;O_2$ were as follows: ${\alpha}-T>{\alpha}-T_3>{\gamma}-T>{\beta}-T>{\gamma}-T_3>{\delta}-T>{\delta}-T_3$. This result showed that ${\alpha}-tocopherol$ among tocochromanols had the lowest antioxidant effect.

• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.8
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• pp.1156-1164
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• 2010

Structured lipids (SLs) were synthesized by enzymatic interesterification with evening primrose oil (EPO) and rice bran oil (RBO) in a batch-type reactor. The interesterification was performed using a water shaker for 24 hr at $55^{\circ}C$. Mixing speed was set at 200 rpm and Lipozyme RM IM (immobilized lipase from Rhizomucor miehei, 10% by weight of total substrates) was used as a biocatalyst. Rice bran oil and evening primrose oil were interesterified with various molar ratios (RBO : EPO, 1:3, 1:4, and 1:5 mol/mol). Reversed-phase high performance liquid chromatography connected with evaporative light-scattering detector was performed to separate the triacylglycerol (TAG) species of SLs. In the fatty acid analysis, $\gamma$-linolenic acid (7.9 mol%), linoleic acid (67.3 mol%) and oleic acid (13.2 mol%) were the most abundant fatty acids in the SLs. During 24 hr reaction, most of the reaction occurred within 3 hr. TAG compositions, tocopherols and phytosterols were also analyzed. In the TAG species analysis, LLL (ECN=42, L=linoleic acid) dramatically decreased when the reaction time increased.

• Asian-Australasian Journal of Animal Sciences
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• v.30 no.11
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• pp.1605-1611
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• 2017

Objective: Following a previous report, an experiment was conducted to determine the effect of increasing level of dried stoned olives pomaces (DSOP) in the diet of lactating buffaloes on milk and mozzarella cheese yield and characteristics. Methods: Sixteen pluriparous buffaloes distributed into two groups were fed an isoenergetic (0.9 milk forage unit/kg) and isoprotein (149 g/kg dry matter [DM] of crude protein) diet, with or without DSOP. Each animal received 17 kg DM/d. Samples of forages and concentrates were weekly collected and used for duplicate chemical analyses. Individual milk samples from each control were analyzed for chemical and coagulating parameters and daily production of mozzarella cheese was estimated. At the end of the trial, bulk milk of each group was processed to produce mozzarella cheese and chemical (fat, protein, ash, pH) composition, fatty acids composition, carotenoids and tocopherols content were determined. A sensory test was also performed. The oxidative stability was measured on mozzarella cheese and on governing liquid. Results: No significant differences were observed, neither for milk yield and body condition score, nor for milk characteristics. The fat was higher (p<0.05) in mozzarella of DSOP fed group but, saturated fatty acids were lower and unsaturated higher (p<0.01). Furthermore, lower atherogenic (p<0.01), and thrombogenic (p<0.05) indices were found in mozzarella cheese of DSOP fed group. In addition, the administration of DSOP did not affect the mozzarella cheese oxidative stability and no negative effect was found in the sensory properties. Conclusion: No contraindications appeared for the inclusion of DSOP in the diet of lactating buffaloes. Besides, important effects on mozzarella cheese quality were obtained, such as a modification of fat content and attributes with an increment in the mono-unsaturated. Additionally, a lower saturated/unsaturated ratio and atherogenic and thrombogenic indices suggest an improvement of dietetic and nutritional characteristics of mozzarella cheese.

• Korean Journal of Food Science and Technology
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• v.41 no.3
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• pp.231-237
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• 2009

Trans free margarine stock (TFMS) was produced by lipase-catalyzed synthesis of fully hydrogenated soybean oil (FHSBO), avocado oil (AO) and palm oil (PO). A blend of FHSBO, AO, and PO with a 1:5:4 (30:150:120 g, respectively) ratio was interesterified with lipozyme RM IM(from Rhizomucor miehei) in a 1 L-batch type reactor at 65 for 12 hr, and the physicochemical and melting properties of TFMS were compared with commercial margarine. The solid fat content (%) of the TFMS was analyzed at 25, 30, and $35^{\circ}C$, respectively, while its melting point was $37.8^{\circ}C$. The trans fatty acid content of the TFMS was below 0.1%. It also had acid, saponification, and iodine values of 0.4, 173.9, and 58.6, respectively. In HPLC chromatograms of the TFMS, newly synthesized peaks of triacylglycerol molecules were observed by using reverse-phase HPLC with evaporative light-scattering detection. Normal-phase HPLC with UV detection was used to quantify tocopherols in the TFMS, indicating that its ${\alpha}-$, ${\gamma}-$ and ${\delta}$-tocopherol contents were 5.7, 2.1, and 1.7 mg/100 g, respectively.

• The Korean Journal of Food And Nutrition
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• v.20 no.2
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• pp.150-157
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• 2007

Hamcho(Salicorinia herbacea, glasswort), a halophyte, is an annual succulent shrub that grows on coastal wetlands and has been regarded as a functional food for good health. Natural dried red and green Hamcho were extracted with 25% ethanol and water at 70$^{\circ}C$. The antioxidant activities of these four extracts were examined by six different assays, including the measurement of total phenolics, radical scavenging effects on 1,1-diphenyl-2-picrylhydrazyl(DPPH), nitric oxide(NO) and nitrite(NO$_2$) scavenging effects, reducing power, and the inhibitory effect on tyrosinase activity. The total phenolic contents of the four extracts were high at 237 ${\sim}$ 255 mg of gallic acid equivalents per 1 g of dried sample tested. The green Hamcho extracts contained more phenolic compounds than the red Hamcho extracts. When they were compared to tocopherols, the antioxidant activities of the green and red Hamcho powders were significantly higher at the same concentration levels(5 mg and 3 mg, respectively) in a POV test. The inhibition effects of the four extracts at a level of 75 ${\mu}l$ were higher than 98% in the POV test. The red Hamcho 25% ethanol extract showed a high significant effect on DPPH radical scavenging(SC$_{50}$, 90.1 ${\mu}l$). The green Hamcho 25% ethanol extract, however, showed a high significant effect on NO radical scavenging(SC$_{50}$, 6.1 ${\mu}l$). The NO$_2$ radical scavenging effect was assayed at pH 1.2, 4.2 and 6.0, and all the Hamcho extracts scavenged the NO$_2$ radical much more effectively at pH 1.2. The NO$_2$ scavenging effect of the red Hamcho 25% ethanol extract(64%) was as high as that of 5 mM vitamin C at pH 1.2(p<0.05). In the reducing power test, the red Hamcho 25% ethanol extract revealed the highest ferric ion reducing activity among the Hamcho extracts, and its activity was as high as that of 0.33 mg/ml of vitamin C. The four Hamcho extracts showed high tyrosinase inhibition effects of more than 80%, and their activities were higher than 50${\mu}$g of kojic acid. The green and red Hamcho 25% ethanol extracts totally inhibited tyrosinase activity(100%). Therefore, the results suggest that red Hamcho extracts may serve as useful natural antioxidants along with green Hamcho extracts.

• Korean Journal of Food Science and Technology
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• v.35 no.3
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• pp.347-352
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• 2003

In order to compare quality characteristics and oxidative stabilities of rice germs prepared under different roasting conditions, sensory evaluation, color value, tocols (tocopherol+tocotrienol) contents, and peroxide value were investigated. Optimum roasting temperatures for the best acceptability were 20, 10, and 6 min at 170, 180 and 190, respectively. Hunter color a values of rice germ increased as roasting temperature and time increased, whereas L value decreased. Peroxide values of unroasted, and roasted rice germs at $170^{\circ}C$ for 20 min, $180^{\circ}C$ for 10 min, and $190^{\circ}C$ for 6 min were 2.0, and 145.6, 169.5, and 182.9 meq/kg, respectively, after 9 days storage at $60^{\circ}C$. Four tocopherol and three tocotrienol isomers were identified, whereas no ${\beta}$-tocotrienol was detected. The major tocopherol and tocotrienol isomers in rice germ were ${\alpha}$-tocopherol and ${\alpha}$-tocotrienol, respectively. ${\alpha}$-Tocopherol content in roasted rice germ decreased significantly during storage, whereas those of ${\beta}$- and ${\gamma}$-tocopherols slowly decreased. ${\delta}$-Tocopherol had the highest stability among tocopherol isomers in roasted rice germ. Similar trends were observed in tocotrienol isomers.

• Applied Biological Chemistry
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• v.38 no.5
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• pp.425-430
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• 1995

The effects of oxidation stability and flavor acceptability of soybean oil by roasting and refining treatment were investigated in this study. The peroxide values of crude oil from unroasted soybean(COUS) were more increased than those of crude oil from unroasted soybean(CORS) during storage under fluorescence light at $45^{\circ}C$. Induction time by the Rancimat Method was 44.9 and above 88.7 hours on COUS and CORS respectively. The order of oxidation stability of oil was crude>degummed>alkali-refining>deodorized>bleached oil in terms of peroxide value, while that of oxidation stability of oil was crude>degummed>deodorized>alkali-refining>bleached oil in regard to induction time by the Rancimat Method. The correlation coefficients between induction time and two charateristics(absorbance of browning reaction products and phosphorous contents) were highly significant, while that between induction time and tocopherol contents was not high during refining stages. The scores for the sensory evaluation of flavor on sesame oil and CORS was 9.269 and 8.269 respectively, but it was not significant between two oils.

• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.8
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• pp.1289-1292
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• 2005

The objective of this study was to characterize and determine contents of vitamin E isomers (alpha-, beta-, gamma-, delta-tocopherols and tocotrienols) in different steamed rice dishes, with or without other grains. Five different rice dishes were evaluated for the vitamin E nutritional value as major Korean staple foods. They were plain steamed rice (SR) and steamed rice mixed with barley (SRBa), red bean (SRRB), black bean (SRBB), or multi-grains (SRMG) containing a mixture of black rice, barley, red beans, and black beans. Vitamin E isomers were extracted from five grams of freeze-dried samples with hexane after saponification. An analytical method, using a normal-phase HPLC with a UV detector, was developed and used to determine the amount of each vitamin E component. The results showed that SR contained three vitamin E isomers (alpha-tocopherol, alpha-tocotrienol, and gamma-tocotrienol). Alpha-tocopherol and gamma-tocotrienol were de-tected from all samples while only SRBB contained beta-tocopherol and beta-tocotrienol. SRMG showed the highest (3.9$\mu$g/g dry wt) and SRRB showed the lowest alpha-tocopherol (1.3$\mu$g/g dry wt) contents. SRBB contained about 5 to 16 times more gamma-tocopherol (19.7$\mu$g/g dry wt) than othe.5. These results suggested that adding black bean or multi-grains can dramatically improve the vitamin E nutritional values compared to the plain steamed rice (SR). Information obtained from this study can be directly related to the amount of vitamin E intake and can be used to balance the diet for Koreans.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.12
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• pp.1817-1826
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• 2014

This study investigated lipid profiles and antioxidant capacities of seven Korean rapeseed cultivars (Naehan, Tamla, Mokpo111, Yeongsan, Tammi, Hanla, and Mokpo68). The rapeseeds contained 29.3~33.2% of extracted lipid and major fatty acids were oleic, linoleic, and linolenic acids. The ratio of omega-6/omega-3 fatty acids was 2.20~3.68 with the highest in Hanla and lowest in Naehan. Glycolipid ranged from 0.21 g/100 g to 0.47 g/100 g. Phospholipid content was 0.55~1.15 g/100 g with the highest in Tammi and the lowest in Mokpo68, and the most common phospholipid was phosphatidylcholine. Tocopherol content was 9.45~15.11 mg/100 g in the order of ${\gamma}$ > ${\alpha}$ > ${\beta}$ > ${\delta}$-tocopherol, and Naehan contained the highest amount of tocopherols (P<0.05). Total phenol content (TPC) of rapeseed was 314.64~577.08 mg SAE/100 g. Tamla contained the highest TPC, and showed the highest antioxidant activity determined by 1,1-diphenyl-2-picrylhydrazyl free radical scavenging capacity and ferric reducing antioxidant power.

• Journal of the Korean Society of Food Science and Nutrition
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• v.46 no.4
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• pp.529-536
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• 2017

Nutritional constituents and physicochemical properties of lipids of forest resources were studied in order to examine their practical utilization in the lipid industry. In this study, Garae, Dongback, Mougwi, and Muwhanja were chosen as sources of fat-soluble components. Fatty acid profiles of forest resources showed more than 80% polyunsaturated fatty acids in total fatty acids. For total tocopherol contents, Garae showed higher content than others; moreover, Dongback was a good source of ${\alpha}$-tocopherol. Phytosterols of forest resources ranged from $55.96{\pm}2.23$ to $194.94{\pm}21.42mg$/100 g, and Muwhanja showed the highest phytosterol contents. Chemical properties such as acid value, peroxide value, and p-anisidine value showed good oxidative stability of lipids of forest resources. For physical properties, browning intensity and color parameters were studied. Induction times, as an indicator of oxidative stability, were measured and ranged from $0.70{\pm}0.01$ to $18.40{\pm}1.02h$ in four forest resources. Taken together, contents of lipid constituents and physicochemical properties can be used as an important preliminary database for utilization of lipids of forest resources.