title: Development of novel zein-sodium caseinate nanoparticle (ZP)-stabilized emulsion films for improved water barrier properties via emulsion/solvent evaporation.
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.
authors.affiliation: Research and Development Center of Food Proteins, Department of Food Science and Technology, South China University of Technology , Guangzhou 510640, PR China.
authors.forename: Li-Juan
authors.initials: LJ
authors.lastname: Wang
authors.forename: Ye-Chong
authors.initials: YC
authors.lastname: Yin
authors.forename: Shou-Wei
authors.initials: SW
authors.lastname: Yin
authors.forename: Xiao-Quan
authors.initials: XQ
authors.lastname: Yang
authors.forename: Wei-Jian
authors.initials: WJ
authors.lastname: Shi
authors.forename: Chuan-He
authors.initials: CH
authors.lastname: Tang
authors.forename: Jin-Mei
authors.initials: JM
authors.lastname: Wang
mesh_terms: D002364:Caseins / Q000737:chemistry*; D004655:Emulsions / Q000138:chemical synthesis / Q000737:chemistry; D018857:Food Packaging / Q000295:instrumentation*; D057927:Hydrophobic and Hydrophilic Interactions; D053758:Nanoparticles / Q000737:chemistry; D010539:Permeability; D011108:Polymers / Q000138:chemical synthesis / Q000737:chemistry; D012997:Solvents / Q000737:chemistry; D013499:Surface Properties; D014867:Water / Q000737:chemistry*; D015028:Zein / Q000737:chemistry*
chemical_list: D002364:Caseins; D004655:Emulsions; D011108:Polymers; D012997:Solvents; D014867:Water; D015028:Zein