title: Light-induced lipid oxidation in sheep milk: effects of dietary grape seed and linseed, alone or in combination, on milk oxidative stability.
abstract: The present work aimed to investigate the milk oxidative stability when the sheep diet includes a source of polyphenols (grape seed, (GS)) and a source of polyunsaturated fatty acids (linseed, (LIN)), alone or in combination (MIX) compared to a control group (CON). For this purpose light-induced oxidation in milk was studied. After 24 h of light exposure the lipid hydroperoxides increased in milk in the LIN and MIX groups. The calculated ratio between the level of lipid hydroperoxides and unsaturated fatty acids (UFAs) in milk was lower in the GS and MIX than in the LIN group. At the same time the level of the ratio between hexanal/linoleic acid in milk was lower in the GS and MIX than in the CON group. Although the dietary inclusion of grape seed did not reduce the level of lipid oxidation products in sheep milk, it effectively reduced the extent of oxidation of UFA.
authors.affiliation: †Dipartimento di Agraria, Sezione di Scienze Zootecniche, University of Sassari, Viale Italia 39, 07100 Sassari, Italy.
authors.forename: Fabio
authors.initials: F
authors.lastname: Correddu
authors.affiliation: †Dipartimento di Agraria, Sezione di Scienze Zootecniche, University of Sassari, Viale Italia 39, 07100 Sassari, Italy.
authors.forename: Anna
authors.initials: A
authors.lastname: Nudda
authors.affiliation: †Dipartimento di Agraria, Sezione di Scienze Zootecniche, University of Sassari, Viale Italia 39, 07100 Sassari, Italy.
authors.forename: Maria G
authors.initials: MG
authors.lastname: Manca
authors.affiliation: †Dipartimento di Agraria, Sezione di Scienze Zootecniche, University of Sassari, Viale Italia 39, 07100 Sassari, Italy.
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Pulina
authors.affiliation: ‡Department of Food Science, Faculty of Science and Technology, Aarhus University, Blichers Allé 20, DK-8830 Tjele, Denmark.
authors.forename: Trine K
authors.initials: TK
authors.lastname: Dalsgaard
mesh_terms: D000821:Animal Feed / Q000032:analysis*; D000818:Animals; D019587:Dietary Supplements / Q000032:analysis; D005231:Fatty Acids, Unsaturated / Q000737:chemistry / Q000378:metabolism; D005260:Female; D019597:Flax / Q000378:metabolism*; D008027:Light; D008055:Lipids / Q000737:chemistry*; D008892:Milk / Q000737:chemistry* / Q000378:metabolism / Q000528:radiation effects; D010084:Oxidation-Reduction / Q000528:radiation effects; D012639:Seeds / Q000378:metabolism*; D012756:Sheep; D027843:Vitis / Q000378:metabolism*
chemical_list: D005231:Fatty Acids, Unsaturated; D008055:Lipids
keywords: antioxidants; grape seed; hydroperoxides; linseed; oxidation; polyphenols; riboflavin; sheep milk