Improvement in properties of edible film through non-thermal treatments and nanocomposite materials: A review

Edible film packaging is recognized as a suitable alternative for maintaining quality and increasing the storage life of foods. Edible films are produced from naturally available polymer sources viz. carbohydrate, protein, lipid, and combination of these. The applicability of biopolymer-based edible films is increasing due to the usage of advanced technologies for improving their structural, physical, mechanical, and barrier properties. Various non thermal techniques, for example, ultrasound, cold plasma, high-pressure processing, and ultraviolet treatments can be efficient to modify the functional properties of edible films. These techniques can improve the properties of films by reducing particle size, strengthening inter-molecular electrostatic repulsion, and increasing the cross linking of biopolymers. Enrichment of nanomaterials in biopolymer matrix can increase the structural and mechanical properties of films through the generation of new hydrogen bonds between nanomaterials and polymers. So, non-thermal techniques and nanomaterials can be useful to improve the properties of edible films.