Chitosan-assisted cinnamaldehyde utilization and sodium carboxymethyl cellulose-enabled redispersion: A dual strategy...

Cinnamaldehyde (CA) is a potent natural antimicrobial but its volatility, poor dispersibility, and dose-dependent cytotoxicity limit use in food coatings. This study proposed a dual strategy for CA stabilization and utilization through chitosan (CS) grafting and sodium carboxymethyl cellulose (CMC) redispersion. CS-CA conjugates were characterized by SEM, TEM, FTIR, XRD, XPS, and ¹H NMR. It was incorporated into CMC to construct CS-CA@CMC composite film through a dual noncovalent network involving hydrogen bonding and electrostatic interactions. The films exhibited UV-shielding (94.82%), 9.05-fold and 1.43-fold higher DPPH and ABTS⁺ scavenging activities than CMC, and achieved >90% inhibition of Acetobacter pasteurianus and Saccharomyces cerevisiae. In detached-stem grape model, the coating extended grape shelf life from 3 to 7 days, reduced decay by 41.2%, and decreased weight loss from 32.6% to 22.9%, while maintaining higher firmness, acidity, and phenolic content. CS-CA conjugate showed low cytotoxicity, indicating potential for biocompatible active packaging.