Biopolymer Development from Agro-Food and Aquaculture By-Products with Antioxidant Hydrolysates of Cyprinus carpio, Produced via Enzymatic Preparations of Pineapple and Papaya

This study describes the development of a biodegradable biopolymer formulated from protein-polysaccharide matrices enriched with antioxidant hydrolysates obtained from <i>Cyprinus carpio</i> by-products. The hydrolysates were produced through targeted enzymatic hydrolysis using plant-derived proteases, yielding peptide fractions with relevant radical-scavenging activity. Molecular characterization (DSC) confirmed the presence of thermal stability suitable for cold-chain applications, while the resulting biopolymer displayed flexible and cohesive structural behavior. The material was evaluated as an edible coating for raspberries stored at 4 °C. Coatings containing the hydrolysates, particularly those generated with bromelain, more effectively slowed physicochemical deterioration, modulated oxidative reactions, and helped to preserve nutritional quality during storage. These findings indicate that integrating bioactive peptide hydrolysates into biodegradable polymer networks enhances their functional performance, offering a sustainable approach for food preservation and valorization of agro-aquaculture residues.