title: Evaluation of antioxidant activity of loquat fruit (Eriobotrya japonica lindl.) skin and the feasibility of their application to improve the oxidative stability of soybean oil.
abstract: The effects of ultrasound-assisted, supercritical CO2 and solvent extraction techniques on antioxidant activity of loqua (Eriobotrya japonica Lindl.) skin extract in oxidation stability of soybean oil was evaluated. The antioxidant efficacy of extracts was determined using 2, 2-diphenyl-1-picrylhydrazyl (DPPH(•)) radical scavenging capacity, β-carotene/linoleic acid, and Rancimat test system. Results showed that solvent extract of loquat fruit skin at 400 ppm had the highest antioxidant activity compared to ultrasound-assisted and supercritical CO2 extracts. Further, solvent extraction was the most effective method for extraction of phenolic compounds. Protective effects of extracts in stabilization of soybean oil during both frying and storage conditions were tested and compared to tert-butyl hydroquinone (TBHQ) by measuring their peroxide value, free fatty acids, conjugated dienes and trienes value. During frying process solvent extract of skin at 400 ppm (SOEA) exhibited stronger antioxidant activity in oil compared to other oil samples, but this antioxidant potential was lower than TBHQ in storage conditions. Present study showed that loquat fruit skin is a good source of natural antioxidant compounds, and has the potential to be used as a substitute for synthetic antioxidants in vegetable oils.
authors.affiliation: Faculty of Food Science and Technology, Gorgan University of Agricultural Sciences and Natural Resources, Gorgan, Iran.
authors.forename: Mojtaba
authors.initials: M
authors.lastname: Delfanian
authors.affiliation: Department of Food Science and Technology, Sari Agriculture and Natural Resources University, Sari, Mazandaran Iran.
authors.forename: Reza Esmaeilzadeh
authors.initials: RE
authors.lastname: Kenari
authors.affiliation: Department of Food Science and Technology, Faculty of Agriculture, Tarbiat Modares University, Tehran, Iran.
authors.forename: Mohammad Ali
authors.initials: MA
authors.lastname: Sahari
keywords: Antioxidant; Deep frying; Eriobotrya japonica; Lipid peroxidation; Soybean oil