Physicochemical Characterization, Antioxidant and Antimicrobial Potential of Biodegradable Chitosan-Based Films Containing Pomegranate (Punica granatum L.) Peel Extract

In this work, the effect of different concentrations of pomegranate peel extract (0.04, 0.07, 0.1 and 0.3%) were evaluated on the physicochemical, morphological and thermal properties, as well as the antioxidant and antimicrobial potential of chitosan films (CHRE-0.04, CHRE-0.07, CHRE-0.1 and CHRE-0.3). The incorporation of the extract did not significantly change the thickness, luminosity or transparency of the films. On the other hand, there was an increase in moisture and water vapor permeability and a decrease in solubility with the increase in the extract concentration added to the films. The films CHRE-0.04 and CHRE-0.07, with lower concentrations of extract, were the ones that demonstrated greater thermal stability. Higher antioxidant activity was obtained by the CHRE-0.3 film, with increases that varied between 5.0 and 36.5 times relative to the film without extract. The film without extract showed greater antimicrobial potential; however, the CHRE-0.3 film was the greatest inhibitor of Escherichia coli (51.6% inhibition). Ecologically friendly chitosan films incorporated with pomegranate peel extract have shown the potential to be used in food preservation as an alternative to conventional packaging.