title: Stabilization mechanism of oil-in-water emulsions by β-lactoglobulin and gum arabic.
abstract: Natural biopolymer stabilized oil-in-water emulsions were formulated using β-lactoglobulin (β-lg), gum arabic (GA), and β-lg:GA solutions as an alternative to synthetic surfactants. Emulsions using these biopolymers and their complexes were formulated varying the biopolymer total concentration, the protein-to-polysaccharide ratio, and the emulsification protocol. This work showed that whereas β-lg enabled the formulation of emulsions at concentration as low as 0.5 (w/w)%, GA allowed to obtain emulsions at concentrations equal to or higher than 2.5 (w/w)%. In order to improve emulsion stability, β-lg and GA were complexed through strong attractive electrostatic interactions. GA solution had to be added to previously prepared β-lg emulsions in order to obtain stable emulsions. Interfacial tension and interfacial rheological measurements allowed a better understanding of the possible stabilizing mechanism. β-lg and GA both induced a very effective decrease in interfacial tension and showed interfacial elastic behaviour. In the mixed system, β-lg adsorbed at the interface and GA electrostatically bound to it, leading to the formation of a bi-layer stabilized emulsion. However, emulsion stability was not improved compared to β-lg stabilized emulsion, probably due to depletion or bridging flocculation.
authors.affiliation: Univ Paris-Sud, UMR CNRS 8612, Faculté de Pharmacie, 5 rue Jean-Baptiste Clément, 92296 Châtenay-Malabry Cedex, France.
authors.forename: Eléonore
authors.initials: E
authors.lastname: Bouyer
authors.forename: Ghozlene
authors.initials: G
authors.lastname: Mekhloufi
authors.forename: Isabelle
authors.initials: I
authors.lastname: Le Potier
authors.forename: Typhaine du Fou
authors.initials: Tdu F
authors.lastname: de Kerdaniel
authors.forename: Jean-Louis
authors.initials: JL
authors.lastname: Grossiord
authors.forename: Véronique
authors.initials: V
authors.lastname: Rosilio
authors.forename: Florence
authors.initials: F
authors.lastname: Agnely
mesh_terms: D004655:Emulsions / Q000737:chemistry; D006170:Gum Arabic / Q000737:chemistry*; D007782:Lactoglobulins / Q000737:chemistry*; D009821:Oils / Q000737:chemistry*; D055672:Static Electricity; D014867:Water / Q000737:chemistry*
chemical_list: D004655:Emulsions; D007782:Lactoglobulins; D009821:Oils; D014867:Water; D006170:Gum Arabic