title: Chemistry of buttermilk solid antioxidant activity.
abstract: Antioxidant activity of buttermilk solids was assessed by analyzing for relative reducing activity, sulfhydryl content, and ferrous and ferric iron binding affinity. These experiments were followed by monitoring the affinity of buttermilk solids to scavenge both hydroxyl and peroxyl radicals in vitro. Notable relative reducing activity of buttermilk solids to L-ascorbic acid (43.80 to 85.85% over a range of 5.0 to 10.0 mg) was attributed in part to the sulfhydryl content (28.8 microM). Buttermilk solids sequestering activity was greater for ferrous than ferric ion. These chemical properties of buttermilk solids corresponded to a significant affinity to scavenge Fenton-induced hydroxyl radical over a range of 5 to 10 mg. A significant affinity of buttermilk solids to protect against lipid peroxidation, tested using an in vitro model lipid system, was also observed at both 0.1 and 0.2% (wt/vol). These findings demonstrated that buttermilk solids possess significant antioxidant activity, thereby suggesting potential use as a value-added ingredient for stabilizing food matrixes against lipid peroxidation reactions.
authors.affiliation: Univ. of British Columbia, 6650 N.W. Marine Drive, Vancouver, British Columbia, Canada V6T 1Z4.
authors.forename: P Y Y
authors.initials: PY
authors.lastname: Wong
authors.forename: D D
authors.initials: DD
authors.lastname: Kitts
mesh_terms: D000818:Animals; D000975:Antioxidants / Q000737:chemistry* / Q000494:pharmacology; D001205:Ascorbic Acid / Q000737:chemistry; D005290:Ferric Compounds / Q000032:analysis / Q000378:metabolism; D005296:Ferrous Compounds / Q000032:analysis / Q000378:metabolism; D016166:Free Radical Scavengers; D017665:Hydroxyl Radical / Q000737:chemistry; D015227:Lipid Peroxidation / Q000187:drug effects; D008892:Milk / Q000737:chemistry*; D010084:Oxidation-Reduction; D013438:Sulfhydryl Compounds / Q000032:analysis
chemical_list: D000975:Antioxidants; D005290:Ferric Compounds; D005296:Ferrous Compounds; D016166:Free Radical Scavengers; D013438:Sulfhydryl Compounds; D017665:Hydroxyl Radical; D001205:Ascorbic Acid