Chitosan film incorporated with citric acid and glycerol as an active packaging material for extension of green chilli shelf life

Abstract

Chitosan films with cross linker and plasticizer were prepared using solvent casting method for food packaging application. Citric acid was used as the cross linker which enhances the stability of the films. Glycerol was used as plasticizer which imparts flexibility. Successful cross linking was confirmed by Fourier Transform-Infra Red (FT-IR) spectra and incorporation of glycerol was seen clearly in the Field Emission Scanning Electron Microscope (FE-SEM) images. The modified films show an improved water resistance and transparency. An improved moisture barrier was also observed with a 5.5% and 29% reduction in water vapor transmission and water vapor permeability, respectively. Modified films showed drastic 12 times increase in the elongation percentage value, hence enhanced flexibility. However, the tensile strength and Young’s modulus decreased substantially by 82% and 98%, respectively. The films also showed better thermal and antioxidant properties as compared to neat chitosan films and were found to enhance green chilli shelf life.