Evaluation of physio-mechanical and antimicrobial properties of indigenously developed food packaging films from corn starch/chitosan incorporated with Fe-NPs and black tea extract.

In this study, bio-composite films were prepared and characterized from a combination of corn starch (CST) loaded with chitosan nanoparticles (CS-NPs), iron nanoparticles (Fe-NPs) and black tea leaves extract (BTE) via the solution casting method. The CS was extracted from shrimp shells and Fe-NPs were synthesized using BTE. The structural characterization of the films was studied using SEM and FTIR analysis, which confirmed the interaction between the film molecules. The thickness of the final CST/CS/Fe/BTE composite film was increased from 0.10 mm to 0.22 mm, the solubility and swelling index declined from 67.3 % to 37.4 % and 52.8 % to 18.0 %, respectively, as compared to the neat CST film. The contact angle and water vapor permeability of the final film were decreased from 96.84 to 75.63 and 6.42 × 10 to 3.63 × 10 g/m/h.kPa after the addition of Fe-NPs and BTE, respectively, which indicates that the prepared films could effectively reduce the moisture diffusion, resulting in extending the shelf-life. Tensile strength and Young's modulus were increased from 25.4 to 75.0 MPa and 120.0 to 458.1 MPa, respectively. The addition of Fe-NPs showed a considerable antimicrobial activity against S. aureus and E. coli. In conclusion, the produced films have promising potential for food packaging applications.