title: Influence of the molecular weight of carboxymethylcellulose on properties and stability of whey protein-stabilized oil-in-water emulsions.
abstract: The influence of the molecular weight (Mw; 270, 750, and 2,500 kDa) and concentration of carboxymethylcellulose (CMC) on the stability and properties of whey protein isolate (WPI)-stabilized oil-in-water emulsions were assessed by measuring ζ-potential, droplet size, apparent viscosity, protein surface coverage, and creaming stability. Emulsions were prepared to contain 5% oil, 0.5% WPI, and 0 to 0.5% CMC at pH 7. After emulsification, pH was adjusted to 5.2. In the absence of CMC, the WPI-stabilized emulsion was unstable to droplet flocculation and coalescence due to the relatively low droplet charge. Emulsions stabilized by mixed WPI-CMC had improved surface properties as well as reduced droplet flocculation, as indicated by increased negative charges and protein surface coverage as well as smaller droplet size. Increased viscosity due to nonadsorbed CMC also contributed to increased stability at high CMC concentration. The high-Mw CMC was more effective in enhancing surface properties and providing better stability against creaming compared with lower-Mw CMC. Maximum stability was achieved with mixed WPI-CMC stabilized emulsion containing 0.08% CMC 2,500 kDa.
authors.affiliation: Food Science Program, Division of Food systems and Bioengineering, University of Missouri, Columbia 65211.
authors.forename: Yan
authors.initials: Y
authors.lastname: Huan
authors.affiliation: Food Science Program, Division of Food systems and Bioengineering, University of Missouri, Columbia 65211.
authors.forename: Sha
authors.initials: S
authors.lastname: Zhang
authors.affiliation: Food Science Program, Division of Food systems and Bioengineering, University of Missouri, Columbia 65211. Electronic address: vardhanabhutib@missouri.edu.
authors.forename: Bongkosh
authors.initials: B
authors.lastname: Vardhanabhuti
mesh_terms: D000818:Animals; D002266:Carboxymethylcellulose Sodium; D004655:Emulsions / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D008894:Milk Proteins / Q000737:chemistry; D008970:Molecular Weight; D014867:Water / Q000737:chemistry; D000067816:Whey Proteins
chemical_list: D004655:Emulsions; D008894:Milk Proteins; D000067816:Whey Proteins; D014867:Water; D002266:Carboxymethylcellulose Sodium
keywords: carboxymethylcellulose; emulsion; molecular weight; whey protein isolate