Cinnamaldehyde enhanced starch/chitosan composite films: A one-pot engineered solution for extended fruit shelf life

Bio-based materials are emerging as promising sustainable alternatives to conventional plastics; however, their application is frequently constrained by inadequate mechanical strength, hydrophobicity, and antimicrobial efficacy. In this study, a multifunctional packaging film was successfully developed by integrating N-isopropylacrylamide (NIPA), alkyl ketene dimer (AKD), and cinnamaldehyde (CIN) into starch (ST)/chitosan (CS) composites through a one-pot synthesis approach. The incorporation of these additives, particularly the synergistic interaction of CIN and the polysaccharide matrix, significantly enhanced the mechanical strength, UV-visible light resistance, and barrier properties of the film. These improvements also contributed to increased antioxidant activity and intrinsic self-reinforcement, thereby improving the film's antimicrobial functionality. Furthermore, the composite film demonstrated excellent biosafety and biodegradability. In practical food preservation tests, bananas wrapped in ST-CIN/NIPA/AKD/CS films demonstrated an extended shelf life of up to 10 days while maintaining quality indicators such as flesh firmness, pH levels, weight loss, and total soluble solids. This work not only presents a novel strategy for improving the performance of biopolymer-based films but also expands the potential applications of polysaccharide-derived natural compounds in sustainable food packaging systems.