title: Protein Fibrils Induce Emulsion Stabilization.
abstract: The behavior of an oil-in-water emulsion was studied in the presence of protein fibrils for a wide range of fibril concentrations by using rheology, diffusing wave spectroscopy, and confocal laser scanning microscopy. Results showed that above a minimum fibril concentration depletion flocculation occurred, leading to oil droplet aggregation and enhanced creaming of the emulsion. Upon further increasing the concentration of the protein fibrils, the emulsions were stabilized. In this stable regime both aggregates of droplets and single droplets are present, and these aggregates are smaller than the aggregates in the flocculated emulsion samples at the lower fibril concentrations. The size of the droplet aggregates in the stabilized emulsions is independent of fibril concentration. In addition, the droplet aggregation was reversible upon dilution both by a pH 2 HCl solution and by a fibril solution at the same concentration. The viscosity of the emulsions containing fibrils was comparable to that of the pure fibril solution. Neither fibril networks nor droplet gel networks were observed in our study. The stabilization mechanism of emulsions containing long protein fibrils at high protein fibril concentrations points toward the mechanism of a kinetic stabilization.
authors.affiliation: Laboratory of Physics and Physical Chemistry of Foods, Department of Agrotechnology and Food Sciences, Wageningen University , P.O. Box 17, 6700 AA, Wageningen, The Netherlands.
authors.forename: Jinfeng
authors.initials: J
authors.lastname: Peng
authors.affiliation: Laboratory of Physics and Physical Chemistry of Foods, Department of Agrotechnology and Food Sciences, Wageningen University , P.O. Box 17, 6700 AA, Wageningen, The Netherlands.
authors.forename: Joana Ralfas
authors.initials: JR
authors.lastname: Simon
authors.affiliation: Laboratory of Physics and Physical Chemistry of Foods, Department of Agrotechnology and Food Sciences, Wageningen University , P.O. Box 17, 6700 AA, Wageningen, The Netherlands.
authors.forename: Paul
authors.initials: P
authors.lastname: Venema
authors.affiliation: Laboratory of Physics and Physical Chemistry of Foods, Department of Agrotechnology and Food Sciences, Wageningen University , P.O. Box 17, 6700 AA, Wageningen, The Netherlands.
authors.forename: Erik
authors.initials: E
authors.lastname: van der Linden
mesh_terms: D004655:Emulsions; D006863:Hydrogen-Ion Concentration; D018613:Microscopy, Confocal; D009821:Oils / Q000737:chemistry*; D014783:Viscosity; D000067816:Whey Proteins / Q000737:chemistry*
chemical_list: D004655:Emulsions; D009821:Oils; D000067816:Whey Proteins