Development and characterization of edible bilayer films based on iron yam–pea starch blend and corn zein

Abstract We prepared bilayer films of iron yam–pea starch and corn zein to evaluate their potential application in the packaging of instant foods and condiments. We found that the water resistance and mechanical properties of bilayer films were improved after adding a layer of corn zein compared with the monolayer films of the starch materials. Scanning electron microscopy revealed that the bilayers were close and this was reflected in increased thermal stability and biocompatibility between layers with the addition of zein. Our experimental films showed greater elongation at break than the commercial biaxially oriented polypropylene polyethylene films. Based on the results of this study, the iron yam-pea starch/corn zein films have the mechanical strength and flexibility to be used for convenience food packaging materials, which are expected to provide consumers with clean products.