Enzymatic Treatments and Thermal Effects on Edible Soy Protein Films

TLDR

The study evaluated how heat and enzymatic treatments affect the physical and moisture barrier properties of soy protein isolate edible films at three plasticizer levels. Enzymatic treatment induces protein degradation and crosslinking. Heat treatment produced smoother, more transparent films with lower water vapor permeability and higher elongation at break and protein solubility, whereas horseradish peroxidase did not further reduce permeability but increased tensile strength and protein solubility and decreased elongation.

Abstract

ABSTRACT The effect of heat and enzymatic treatments on physical and moisture barrier properties of soy protein isolate (SPI) edible films were evaluated at three plasticizer levels. Heat treatment produced a film which was smoother and more transparent than unheated SPI films. Heated films had decreased water vapor permeability (WVP) and increased % elongation at break (%E) and % soluble protein when compared to unheated films. Treatment with horseradish peroxidase provided no further improvement in WVP, but increased tensile strength and % protein solubility and decreased %E. Enzymatic treatment caused protein degradation in addition to crosslinking.