Characterization of Chitosan-Based Edible Films for Food Packaging Applications

Aims: To study the optimization and characterization of chitosan-based edible films for food packaging applications Study Design: This study was experimental and conducted in a lab. Place and Duration of Study: The study was conducted at the Department of Dairy Technology, Dairy Science College, Hebbal, Bengaluru, Karnataka, India, between October 2022 and July 2023. Methodology: The edible film was developed with 9 different combinations by 3 concentrations of chitosan 1.50, 2.0 and 2.5% along with 3 concentrations of glycerol 0.5, 0.75 and 1%. Various characteristics like moisture content, water solubility, thickness, density, GSM, colour, transmittance, water vapor transmission rate (WVTR), tensile strength, elongation are assessed. The film was optimised on the basis of water vapor transmission rate, tensile strength and elongation. ANOVA was the method used for statistical analysis, and the significance between the control and sample was assessed using a critical difference (CD) at a 5% significance level. Results: Increase in chitosan concentration the film thickness, GSM, solubility and density increases whereas moisture content decreases. Increase in glycerol concentration the film thickness, GSM, moisture, solubility increases but there was decrease in film density. The film colour parameters lightness L*, redness a* and yellowness b* increase as chitosan content increases, whereas transmittance decreases. Increased glycerol content increased the film's colour parameters redness a* and transmittance, but had no influence on the film's yellowness whereas as the lightness value decreases. The film made with 2.5% chitosan and 0.5% glycerol has the lowest water vapour transmission rate, 10.70 g/m2h. The tensile strength of film made with 2.5% chitosan and 0.5% glycerol has the highest value of 18.56 MPa. Film produced using 1.5% chitosan and 1% glycerol has the highest value of 51.73% elongation. Conclusion: Increasing the concentration of chitosan improves tensile strength but reduces elongation. On the other hand, adding more glycerol lowers tensile strength but increases elongation. A film containing 2% chitosan and 0.75% glycerol is considered the best choice, offering a balanced water vapor transfer rate, tensile strength, and elongation.