Active naringin-chitosan films: impact of UV irradiation

Bioactive citrus extract-chitosan films were prepared through solvent casting-evaporation method. The impact of near UV irradiation was studied to reach a better understanding of the film behavior. The antimicrobial activity of films against Listeria innocua was maintained after UV irradiation. To study the interaction between chitosan and citrus extract components, naringin (main component) was selected as the model compound. UV treatment caused modifications of the flavanone regardless of the solvent used for its dissolution, depending on the concentration of naringin in the film: the greater the concentration the lower the modification. DSC results suggested cross-links due to UV irradiation and interactions between naringin and chitosan. This was confirmed by a decrease in the naringin release from the irradiated samples. Naringin- and citrus extract-chitosan films showed an increased absorbance in the UV region compared to pure chitosan films, showing potentiality for decreasing the lipid oxidation induced by UV light in foodstuffs.