• Journal of the Korean Society of Food Culture
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• v.19 no.4
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• pp.399-406
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• 2004

The extracts 70% acetone from chestnut inner shell, pine needle and hop flower were added to soybean oil, lard, soybean oil-water emulsion and lard-water emulsion in order to test the antioxidant activity compared with ${\alpha}-tocopherol$, respectively. Induction period was determined by Rancimat and the antioxidant activities were recorded in the order of pine needle>chestnut inner shell>hop>tocopherol in the soybean oil, and in the order of tocopherol>chestnut inner shell>pine needle>hop in the lard treatment. These three extracts showed similar high antioxidant activity by peroxide value test in soybean oil, soybean oil-water emulsion, lard and lard water emulsion, respectively. The chestnut inner shell extract would be the highest antioxidant agent among the extracts tested in this study. Ellagic acid of chestnut inner shell and flavanol of pine needle would increase the antioxidant activity according to analysis result of polyphenol compound, respectively.

• Food Science and Preservation
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• v.7 no.4
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• pp.373-379
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• 2000

The Ulmi corex extract was prepared using various solvents to investigate the availability as a natural antioxidant. The extracts were added to lard emulsion and the antioxidant activities were compared. The extract that had a greater antioxidant activity was fractionized. Then the antioxidant activity and substrate specificity of the fraction were examined and optimum concentration of addition was determined. To observe the antioxidative effect of the fraction in vivo, an inhibition rate of lipid peroxidation from which might be derived was measured using a microsome in rat's liver. Among the extracts of Ulmi cortex, the extract from water had the best antioxidant activity, and the addition of 0.05% (w/w) of ethyl acetate fraction showed similar antioxidant activity to a synthetic antioxidant, butylated hydroxyanisole(BHA). Ethyl acetate fraction (0.05%, w/w) also presented the antioxidative effect in lard, soybean oil, palm oil, and com oil. The inhibition of lipid peroxidation in liver microsome showed feater in the ethyl acetate fraction than caffeic acid in both nonenzymatic peroxidation (Fe$\^$++/ascorbate system) and enzymatic peroxidation (Fe$\^$++/-ADP/NaDPH system).

• Journal of the Korean Society of Food Science and Nutrition
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• v.21 no.6
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• pp.693-700
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• 1992

As an approach to study a new natural antioxidant for edible fats and oils, antioxidative fractions from acorn powder were characterized. The oxidative stabilities of soybean, palm, beef tallow, and lard oil containing the acorn active fraction extracted with various organic solvents were studied by determining the peroxide value during the storage at $60^{\circ}C.$ And this effective antioxidative components were isolated and identified by thin layer chromatography and high performance liquid chromatography. The proximate compositions of acorn powder were water 11.9~12.0%, protein 7.1~7.4%, starch 65.5~69.4%, fat 2.1~2.6%, fiber 2.1~3.6%, ash 2.4~2.6%, and total tannin 4.6~6.8%, respectively. The final yield of fraction extracted by sequential order of acetone : $H_2O$(1 : 1) and ethylacetate was 2.8~3.1%. Gallic acid, digallic acid and gallotannin were contained this final fraction. The main antioxidative activity was speculated due to the presence of gallic acid in acorn powder extract. The antioxidative activity was more effective in fat water emulsion than just fat system. Antioxidative activities measured by peroxide value were quite high in beef tallow and soybean emulsion, but low in lard and palm oil emulsion in the concentration of 200ppm acorn extract. Therefore, the addition of 200ppm acorn extract was suggested to expect effective antioxidation concentration in the reaction system.