Versatile corn starch-based sustainable food packaging with enhanced antimicrobial activity and preservative properties

Biodegradable active packaging has garnered significant research interest owing to growing concerns over plastic pollution and food safety. However, current food packaging materials still suffer from drawbacks such as complex synthesis processes, high production costs, and inadequate safety performance in terms of antimicrobial resistance and biodegradability. Typically, their performance in preserving fresh food is also inferior to that of plastics. Herein, a versatile corn starch-based sustainable food packaging (DC) was proposed, utilizing natural corn starch (CS) and carboxymethyl chitosan (CMCS) as raw materials. The focus was on evaluating the mechanical properties, antioxidant properties, and antimicrobial activity, and to further explore the degradability and biocompatibility of the DC films, as well as their application in fruit preservation. The results confirmed the good water vapor barrier properties, antioxidant activity (DPPH scavenging of the DC4 film reached 98.10 ± 0.32 %), Ultraviolet (UV) resistance (more than 99.8 % absorption of both UV-A and UV-B radiation), water resistance, mechanical properties, and bacteriostatic and bactericidal effect (the DC4 film reached 99.67 ± 0.58 % against Escherichia coli and 99.83 ± 0.29 % against Staphylococcus aureus) of the DC. Meanwhile, the DC exhibited favorable biodegradability in the natural environment. Finally, fruit preservation experiments confirmed that the DC could significantly extend the shelf life of fresh fruits at room temperature. Overall, this research presented a sustainable and cost-effective biomass-derived packaging film that could replace conventional petroleum-based plastics, thereby reducing environmental pollution and showing significant potential for use in food packaging.