Physicochemical and microstructural properties of composite edible film obtained by complex coacervation between chitosan and whey protein isolate

The aim of this work was to study the potential application edible films obtained by complex coacervation promoted electrostatic interactions between positively charged chitosan (CH) 3% (w/w) and negatively whey protein isolate (WPI) (w/w). Preliminary assays turbidimetry were made in order find optimal CH-to-WPI mass ratio for coacervation. maximum turbidity CH:WPI 0.1:1 dispersions CH/WPI (both at (w/w)), WPI 5% CH analyzed Cryo-scanning electron microscopy (Cryo-SEM) micrograph coacervate presented a more compact network structure than individual biopolymers. composite prepared, characterized their performance physicochemical properties compared with those or films, terms water vapor permeability (WVP), mechanical properties, solubility, sorption isotherms, optical scanning (SEM) imaging, Fourier-transform infrared spectroscopy (FTIR) differential calorimetry (DSC). Results revealed that incorporation small amounts matrix led form film higher tensile strength, lower deformation, malleability, flexibility, solubility WVP comparison mono-component films. resulted decrease equilibrium moisture content Guggenheim-Anderson-de Boer (GAB) model data indicated isotherms type II. All homogeneous structure, color transparency, which is desired food applications packaging technology.