Preparation of composite film with CoFe2O4/MXene/chitosan for extending the shelf life of Kyoho grapes

In this study, a composite film, CFO/MXene nanoenzymes (CM), was designed through the hydrothermal method using CoFe2O4 (CFO) and MXnen with two-dimensional structure as the raw materials to effectively extend the shelf life of Kyoho grapes. The antibacterial rate of CM was 57.3% and 32.6% higher than that of MXene and CFO, respectively. Briefly, 1, 3, 5, and 7 vol% of CM were compounded into 70 mL (3 wt%) of chitosan (CS) solution and heated at 50 °C for 5 h to prepare a novel type of CS/CM composite film. The TEM and SEM results showed that CM was uniformly dispersed in the CS matrix. Compared with the CS film, the elongation at break (EB) and tensile strength (TS) of the CS/5% CM film were increased by 161.53% and 54.08%, respectively. The antibacterial activities of the CS/5% CM film against E. coli, S. aureus, and Aspergillus niger were 99.7%, 99.8%, and 97.1%, respectively. The experimental results demonstrated that the CS/5% CM film had better mechanical and antibacterial properties than the CS film, and the CS/5% CM film could reduce the loss of nutrients in grapes during the preservation of Kyoho grapes. Overall, the CS/5% CM film has the potential to extend the shelf life of Kyoho grapes as a packaging material with good application prospects in the field of food preservation. [Display omitted] •With excellent bacteriostatic properties, CM was first used in food preservation.•CM can optimize the mechanical and antibacterial properties of the film.•CS/5% CM has both high toughness and hardness.•CS/5% CM has stronger freshness retention effect than traditional PE film.