Valorization of Quince By-Products Using Natural Deep Eutectic Solvents (NADES): Extraction and In Vitro Digestion of Phenolic Compounds

Quince (Cydonia oblonga Mill.) processing generates peel and core by-product fractions that are underexploited resources with untapped potential for valorization in sustainable food systems. In this study, ultrasound-assisted extraction was performed using several choline chloride-based natural deep eutectic solvents (NADES, six formulations with distinct hydrogen-bond donors) and compared with 70% (v/v) ethanol. Extracts were analyzed for total phenolic content, antioxidant capacity, and...