title: Anthocyanin antioxidant activity and partition behavior in whey protein emulsion.
abstract: The antioxidant activities of anthocyanins and anthocyanin fractions isolated from blackcurrants, raspberries, and lingonberries were investigated in whey protein-stabilized emulsion. The extent of protein oxidation was measured by determining the loss of tryptophan fluorescence and formation of protein carbonyl compounds and that of lipid oxidation by conjugated diene hydroperoxides and hexanal analyses. The antioxidant activity of berry anthocyanins increased with an increase in concentration. Blackcurrant anthocyanins were the most potent antioxidants toward both protein and lipid oxidation at all concentrations due to the beneficial combination of delphinidin and cyanidin glycosides. Most berry anthocyanins (69.4-72.8%) partitioned into the aqueous phase of the emulsion, thus being located favorably for antioxidant action toward protein oxidation. The presence of the lipid decreased the share of anthocyanin in the aqueous phase. Thus, the structure of food affects the antioxidant activity by influencing the partitioning of the antioxidant.
authors.affiliation: Department of Applied Chemistry and Microbiology, Division of Food Chemistry, University of Helsinki, P.O. Box 27, FIN-00014 Helsinki, Finland. kaarina.viljanen@helsinki.fi
authors.forename: Kaarina
authors.initials: K
authors.lastname: Viljanen
authors.forename: Petri
authors.initials: P
authors.lastname: Kylli
authors.forename: Eva-Maria
authors.initials: EM
authors.lastname: Hubbermann
authors.forename: Karin
authors.initials: K
authors.lastname: Schwarz
authors.forename: Marina
authors.initials: M
authors.lastname: Heinonen
mesh_terms: D000872:Anthocyanins / Q000032:analysis / Q000494:pharmacology*; D000975:Antioxidants / Q000032:analysis / Q000494:pharmacology*; D055598:Chemical Phenomena; D002627:Chemistry, Physical; D004655:Emulsions / Q000737:chemistry*; D015227:Lipid Peroxidation / Q000187:drug effects; D008894:Milk Proteins / Q000737:chemistry*; D010084:Oxidation-Reduction; D011506:Proteins / Q000737:chemistry; D031965:Ribes / Q000737:chemistry; D027824:Rosaceae / Q000737:chemistry; D014364:Tryptophan / Q000737:chemistry; D029801:Vaccinium vitis-idaea / Q000737:chemistry; D000067816:Whey Proteins
chemical_list: D000872:Anthocyanins; D000975:Antioxidants; D004655:Emulsions; D008894:Milk Proteins; D011506:Proteins; D000067816:Whey Proteins; D014364:Tryptophan