Cili pomace-enhanced chitosan/cellulose nanofibril composite films for antioxidant, antibacterial, and biodegradable food packaging

Cili (Rosa roxburghii Tratt.) pomace is rich in bioactive components, making it a promising additive for functional packaging materials. Cili pomace extracts (CLPE) were incorporated into chitosan/cellulose nanofibril (CS/CNF) matrices to develop a food packaging material-strong intermolecular hydrogen bonding among CS, CNF, and CLPE, leading to amorphous structural features. The CS/CNF/CLPE composite films, particularly those with 20 % CLPE loading, displayed significantly reduced water vapour permeability (WVP), enhanced thermal stability, and superior UV-blocking capacity. Additionally, the enrichment of CLPE endowed the composite films with potent functional properties, enhancing their antibacterial efficacy against Escherichia coli and Staphylococcus aureus. In strawberry preservation tests, the CS/CNF/20 %CLPE film solution inhibited decay, minimised weight loss, and maintained fruit quality. Additionally, films containing CLPE accelerated biodegradation, with over 70 % degradation occurring within 21 d. Therefore, the multifunctional CS/CNF/CLPE composite film, which leverages the valorisation of agricultural by-products, presents a promising sustainable packaging candidate for active food preservation.