Physical, Mechanical, Barrier, and Optical Properties of Sodium Alginate/Gum Arabic/Gluten Edible Films Plasticized with Glycerol and Sorbitol

This study aimed to produce sodium alginate/gum Arabic/gluten edible films and to evaluate the effect of glycerol and sorbitol in various concentrations on the physical, mechanical, barrier, and optical properties of the films. Using solvent casting, an edible film based on sodium alginate/gum Arabic/gluten was plasticized with glycerol and sorbitol at 2%, 4%, and 6% (w/v). The properties of edible films were then characterized by physical, mechanical, barrier, and optical properties. Decreased solubility, tensile strength, and water vapor transmission rate were obtained as higher glycerol and sorbitol concentrations were added. Films plasticized with 6% glycerol and 6% sorbitol had the lowest solubility, tensile strength, and water vapor transmission rate. In addition, films plasticized with glycerol, regardless of concentration, were more transparent than sorbitol. Still, the addition of glycerol and sorbitol was insignificant in the thickness properties and L value of the films. The absorption peaks of the Fourier transform infrared spectra pattern of films plasticized with sorbitol and glycerol were similar, confirming the interaction between plasticizers and biopolymers used in this study. Sorbitol and glycerol are compatible with sodium alginate/gum Arabic/gluten, and it is confirmed that these plasticizers influence the films' physical, mechanical, barrier, and optical properties.