Development of Quince Peel Extract Loaded Chitosan/PVA-Based Edible Films for Food Coating

This study aimed to valorize quince peel (Cydonia oblonga Mill.) as an agro-industrial by-product by recovering phenolic compounds through ultrasound-assisted extraction (UAE) and incorporating the optimized extract into chitosan/polyvinyl alcohol (PVA)-based edible films. Extraction parameters (temperature [°C], extraction time [min], HCl concentration [M], and ethanol concentration [%, v/v]) were optimized using response surface methodology (RSM) combined with a central composite design (CCD). The developed quadratic models showed high determination coefficients (R² = 0.9664, 0.9394, and 0.9793 for total phenolic content, ABTS, and FRAP, respectively), confirming the reliability of the predictive models. The optimized conditions yielded 23.90 mg GAE/g QP total phenolic content and antioxidant capacities of 9.56 mg TE/g QP (ABTS) and 18.64 mg TE/g QP (FRAP). The extract with the highest antioxidant capacity was incorporated into chitosan/PVA films via solvent casting. Structural analyses (FT-IR and SEM) confirmed strong intermolecular interactions and good compatibility between the extract and polymer matrix. The incorporation of quince peel extract improved the water vapor barrier properties and flexibility of the films, while slightly reducing tensile strength. The developed edible coating was applied to fresh-cut pineapple and stored at 4°C for 14 days. Coated samples, particularly those containing the extract, exhibited better visual quality preservation and higher total phenolic and antioxidant capacity compared to uncoated controls. These findings demonstrate that quince peel extract can be effectively recovered using optimized UAE and successfully utilized as a functional bioactive component in biodegradable edible films, contributing to sustainable food packaging applications.