Development of novel zein-sodium caseinate nanoparticle (ZP)-stabilized emulsion films for improved water barrier properties via emulsion/solvent evaporation

J Agric Food Chem. 2013 Nov 20;61(46):11089-97. doi: 10.1021/jf4029943. Epub 2013 Nov 12.

Abstract

This work attempted to develop novel high barrier zein/SC nanoparticle (ZP)-stabilized emulsion films through microfluidic emulsification (ZPE films) or in combination with solvent (ethyl acetate) evaporation techniques (ZPE-EA films). Some physical properties, including tensile and optical properties, water vapor permeability (WVP), and surface hydrophobicity, as well as the microstructure of ZP-stabilized emulsion films were evaluated and compared with SC emulsion (SCE) films. The emulsion/solvent evaporation approach reduced lipid droplets of ZP-stabilized emulsions, and lipid droplets of ZP-stabilized emulsions were similar to or slightly lower than that of SC emulsions. However, ZP- and SC-stabilized emulsion films exhibited a completely different microstructure, nanoscalar lipid droplets were homogeneously distributed in the ZPE film matrix and interpenetrating protein-oil complex networks occurred within ZPE-EA films, whereas SCE films presented a heterogeneous microstructure. The different stabilization mechanisms against creaming or coalescence during film formation accounted for the preceding discrepancy of the microstructures between ZP-and SC-stabilized emulsion films. Interestingly, ZP-stabilized emulsion films exhibited a better water barrier efficiency, and the WVP values were only 40-50% of SCE films. A schematic representation for the formation of ZP-stabilized emulsion films was proposed to relate the physical performance of the films with their microstructure and to elucidate the possible forming mechanism of the films.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Caseins / chemistry*
  • Emulsions / chemical synthesis
  • Emulsions / chemistry
  • Food Packaging / instrumentation*
  • Hydrophobic and Hydrophilic Interactions
  • Nanoparticles / chemistry
  • Permeability
  • Polymers / chemical synthesis
  • Polymers / chemistry
  • Solvents / chemistry
  • Surface Properties
  • Water / chemistry*
  • Zein / chemistry*

Substances

  • Caseins
  • Emulsions
  • Polymers
  • Solvents
  • Water
  • Zein