Film‐forming Mechanism and Heat Denaturation Effects on the Physical and Chemical Properties of Pea‐Protein‐Isolate Edible Films

ABSTRACT Pea‐protein isolate solutions were heat‐denatured and dried to form stand‐alone edible films. Heat treatment at 90 °C over 5 min increased tensile strength and elongation‐at‐break, and decreased the elastic modulus. No significant differences were found in the initial contact angle of water and surface energies of heat‐denatured films from those of nonheated films except for the 20 min heat‐treated film. Additionally, heat denaturation reduced the water absorption rate of the films to 19 to 40% of the nonheated film. FTIR spectroscopy showed that more water existed in the nonheated films as compared to the heat‐denatured films. Electrophoresis studies suggested that intermolecular disulfide bonds were created during heat denaturation, which resulted in increased film integrity.