title: Effect of α-lactalbumin and β-lactoglobulin on the oxidative stability of 10% fish oil-in-water emulsions depends on pH.
abstract: The objective of this study was to investigate the influence of pH on lipid oxidation and protein partitioning in 10% fish oil-in-water emulsions prepared with different whey protein isolates with varying ratios of α-lactalbumin and β-lactoglobulin. Results showed that an increase in pH increased lipid oxidation irrespective of the emulsifier used. At pH 4, lipid oxidation was not affected by the type of whey protein emulsifier used or the partitioning of proteins between the interface and the water phase. However, at pH 7 the emulsifier with the highest concentration of β-lactoglobulin protected more effectively against oxidation during emulsion production, whereas the emulsions with the highest concentration of α-lactalbumin were most stable to oxidation during storage. These differences were explained by differences in the pressure and adsorption induced unfolding of the individual protein components.
authors.affiliation: Division of Industrial Food Research, National Food Institute, Technical University of Denmark, DK-2800 Kgs. Lyngby, Denmark.
authors.forename: Anna Frisenfeldt
authors.initials: AF
authors.lastname: Horn
authors.forename: Tune
authors.initials: T
authors.lastname: Wulff
authors.forename: Nina Skall
authors.initials: NS
authors.lastname: Nielsen
authors.forename: Charlotte
authors.initials: C
authors.lastname: Jacobsen
mesh_terms: D000818:Animals; D004655:Emulsions / Q000737:chemistry; D005395:Fish Oils / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D007768:Lactalbumin / Q000737:chemistry*; D007782:Lactoglobulins / Q000737:chemistry*; D008894:Milk Proteins / Q000737:chemistry; D010084:Oxidation-Reduction; D055550:Protein Stability; D014867:Water / Q000737:chemistry; D000067816:Whey Proteins
chemical_list: D004655:Emulsions; D005395:Fish Oils; D007782:Lactoglobulins; D008894:Milk Proteins; D000067816:Whey Proteins; D014867:Water; D007768:Lactalbumin