Self-assembled Chitosan-based Antibacterial Films And Their Freshness Preservation Performance On Fruits And Pork

With the increasing emphasis on food safety and the quality of the food itself,more and more perishable fruits and meats are being wasted due to their short shelf life.Therefore,a simple and efficient active antimicrobial cling film to extend the shelf life has become a hot research topic in the field of food preservation and food packaging.In this paper,the active antimicrobial packaging film was prepared by self-assembling organic antimicrobial agent tannic acid and inorganic antimicrobial agent zinc ion with green and safe chitosan and its derivatives as film-forming materials.Firstly,MXene and tannic acid were introduced into the chitosan solution by electrostatic self-assembly to develop a composite film with excellent antibacterial and antioxidant properties,and the interaction of the components in the film was tested for material characterization,while its mechanical and barrier properties,as well as antibacterial and antioxidant properties,were tested and analyzed correspondingly,and finally,the effect of the composite film on actual fruits banana and The effects of the composite films on the freshness of banana and grape were investigated.The results confirmed that the mechanical properties,water resistance,antibacterial properties and antioxidant properties of the composite films formed by electrostatic self-assembly were significantly improved to meet the scenarios of fruit packaging materials.The experiments on bananas and grapes also confirmed that the composite film can effectively extend the shelf life of bananas and grapes through its excellent water vapor and oxygen barrier as well as antibacterial and antioxidant properties to achieve the freshness of the fruits.Next,a composite film with excellent antibacterial properties and excellent water resistance was designed by bringing zinc ions into the anionic system of carboxymethyl chitosan and sodium alginate through adsorption self-assembly.The reasons for the high-water resistance and antimicrobial properties of the composite film were also determined by testing and analyzing the water resistance and antimicrobial properties as well as characterizing the internal interactions of the materials themselves.The experiments on cold pork preservation also proved that the composite film can significantly extend the shelf life of pork through its good barrier performance and antimicrobial property,and achieve the effect of preservation.Finally,by analyzing the preservation performance of active antimicrobial packaging films,it was found that packaging films with active antimicrobial properties can significantly extend the shelf life of fruits and pork,and these characteristics make antimicrobial packaging films appear as a competitive packaging material in the field of food preservation and packaging,and suggest new solutions to the problem of short shelf life of perishable foods.