Release behavior of quercetin from chitosan-fish gelatin edible films influenced by electron beam irradiation

• Irradiation was applied to edible chitosan-gelatin films.
• Irradiation generated reversible interactions between quercetin and polymer matrix.
• Irradiation delayed the release and increased the quercetin retention.
• Irradiation did not modify the rate of diffusion.

This work dealt with the study of the release kinetics of quercetin incorporated into chitosan-gelatin edible films after electron beam irradiation. The aim was to determine the influence of irradiation dose (at 40 and 60 kGy) on the retention of quercetin in the films, their release in a hydroalcoholic medium (30% ethanol v/v) at 25 °C. Irradiation induced a reduction of the release rate for quercetin, revealing that cross-linking probably occurred during irradiation. Indeed, the content (%) of quercetin remaining in the film after the release increased from 23.4 ± 5.7% for non-irradiated sample to 33.6 ± 2.1% after a 60 kGy irradiation dose. But the effective diffusion coefficient of quercetin was not significantly modified by the irradiation process. However, it was noticed a significant increase of the lag-time (time required before the release starts) by ten times. Thus, the irradiation influenced the retention by creating new interactions or linkages between biopolymers and the quercetin, which finally led to an entrapment of a significant amount of the antioxidant. As expected, the electron beam irradiation allowed modulating the retention and then the release of the antioxidant encapsulated in the chitosan-gelatin matrices.