Essential oils-loaded electrospun chitosan-poly(vinyl alcohol) nonwovens laminated on chitosan film as bilayer bioactive edible films

Abstract

Direct application of active and volatile compounds of essential oils (EOs) is ineffective in food and uncontrolled release of these compounds may be undesirable from sensory and antimicrobial efficacy standpoints. The present study aimed to develop and characterize the physical and antimicrobial properties of casting composite chitosan (CS) thin films laminated with electrospun nonwovens loaded with Zataria multiflora (ZEO) and cinnamon (CEO) targeting for active food packaging purposes. The composite structures were incorporated with various amounts of ZEO and CEO blend to enhance their antimicrobial and physical properties. There was no significant difference between antibacterial activity of the films containing EOs in both Gram-positive and Gram-negative bacteria (P˂0.05). All the films had antifungal activity against A.flavus. The highest antioxidant activity was found in the composite CS film (97.20%) in comparison to other films (P˂0.05). Morphological analysis of bilayer films revealed homogeneous bead-free electrospun nanofibers with diameters of less than 200 nm. The addition of 0.5 %v/v CEO significantly enhanced the elongation in comparison to CS film (P˂0.05). Our results demonstrated that the properties of bilayer films were influenced by the contents of EOs and these findings may pave a way for introducing new category of active packaging staffs.