Chitosan quaternary ammonium salt/gelatin-based biopolymer film with multifunctional preservation for perishable products

The postharvest physiological and metabolic activities caused fruits and vegetables (F&V) quality deterioration. Therefore, developing an efficient preservation strategy is a promising approach to relieve this issue. In this study, a modified metal-organic framework (MOF; i.e., Cer@MHKUST-1) was encapsulated into a blended matrix of chitosan quaternary ammonium salt (CQAS)/gelatin to fabricate a multifunctional (water-locking, ethylene-removing, and antibacterial) packaging biopolymer-based film (i.e., CMCGF), the characteristics and preserva-tive effects of the packaging were investigated. Results indicated that the physicochemical (e.g., mechanical, gas/ light barrier, wettability) properties of CMCGF were improved compared with the control film (i.e., CGF). CMCGF have a higher ethylene adsorption performance of 65-69 cm3/g STP compared with CGF (7.8 cm3/g STP). Cu ions released from CMCGF destroyed the cell wall and membrane, resulting in the death of bacteria, and the antibacterial efficiency of CMCGF against E. coli and S. aureus was 97-100 % and 98-100 %, respectively. Postharvest storage experiments on tomato and winter jujube confirmed the high-efficiency preservation effect of CMCGF packaging. Therefore, CMCGF provides a multifunctional approach to extending the shelf-life of perishable products to decrease food wastage.

Automated summary

In this study, a multifunctional packaging biopolymer-based film (CMCGF) was developed using a modified metal-organic framework (MOF) and a blended matrix of chitosan quaternary ammonium salt (CQAS)/gelatin. The CMCGF film showed improved physicochemical properties and had a higher ethylene adsorption performance compared to the control film (CGF). The release of Cu ions from CMCGF resulted in bacterial death, with an antibacterial efficiency of 97-100% against E. coli and 98-100% against S. aureus. Postharvest storage experiments confirmed the high-efficiency preservation effect of CMCGF packaging on tomato and winter jujube. Therefore, CMCGF provides a multifunctional approach to extend the shelf-life of perishable products and reduce food wastage.