title: Value-added potential of expeller-pressed canola oil refining: characterization of sinapic acid derivatives and tocopherols from byproducts.
abstract: Valuable phenolic antioxidants are lost during oil refining, but evaluation of their occurrence in refining byproducts is lacking. Rapeseed and canola oil are both rich sources of sinapic acid derivatives and tocopherols. The retention and loss of sinapic acid derivatives and tocopherols in commercially produced expeller-pressed canola oils subjected to various refining steps and the respective byproducts were investigated. Loss of canolol (3) and tocopherols were observed during bleaching (84.9%) and deodorization (37.6%), respectively. Sinapic acid (2) (42.9 μg/g), sinapine (1) (199 μg/g), and canolol (344 μg/g) were found in the refining byproducts, namely, soap stock, spent bleaching clay, and wash water, for the first time. Tocopherols (3.75 mg/g) and other nonidentified phenolic compounds (2.7 mg sinapic acid equivalent/g) were found in deodistillates, a byproduct of deodorization. DPPH radical scavenging confirmed the antioxidant potential of the byproducts. This study confirms the value-added potential of byproducts of refining as sources of endogenous phenolics.
authors.affiliation: Department of Human Nutritional Sciences, University of Manitoba , Winnipeg, Manitoba R3T 2N2, Canada.
authors.forename: Yougui
authors.initials: Y
authors.lastname: Chen
authors.forename: Usha
authors.initials: U
authors.lastname: Thiyam-Hollander
authors.forename: Veronique J
authors.initials: VJ
authors.lastname: Barthet
authors.forename: Ayyappan A
authors.initials: AA
authors.lastname: Aachary
mesh_terms: D000975:Antioxidants / Q000032:analysis / Q000494:pharmacology; D002794:Choline / Q000031:analogs & derivatives / Q000737:chemistry; D003373:Coumaric Acids / Q000737:chemistry*; D005229:Fatty Acids, Monounsaturated / Q000737:chemistry*; D005524:Food Technology / Q000379:methods*; D010636:Phenols / Q000737:chemistry; D000074262:Rapeseed Oil; D024505:Tocopherols / Q000032:analysis / Q000737:chemistry*; D014753:Vinyl Compounds / Q000737:chemistry
chemical_list: D000975:Antioxidants; D003373:Coumaric Acids; D005229:Fatty Acids, Monounsaturated; D010636:Phenols; D000074262:Rapeseed Oil; D014753:Vinyl Compounds; C005685:sinapine; C073734:sinapinic acid; D002794:Choline; D024505:Tocopherols; C488411:4-vinyl-2,6-dimethoxyphenol
keywords: antioxidant activity; expeller-pressed canola oil; phenolics; refining byproducts; tocopherol