Dual-functional intelligent gelatin based packaging film for maintaining and monitoring the shrimp freshness

Dual-functional intelligent food packaging film for maintaining and monitoring food freshness has gained a growing number of attentions in food field. Herein, we introduced a smart gelatin-based packaging film integrating real-time monitoring and maintaining food freshness. In detail, through a two-step de-solvation method, gelatin particles were fabricated and further used for preparing oil-in-water (O/W) lavender essential oil Pickering emulsions (LEOPs). LEOPs and Alizarin (ALI) were integrated into the gelatin matrix of the three-dimensional (3D) network via intermolecular hydrogen bonding and dehydration condensation, respectively, to develop intelligent active packaging films (GL-ALI-LEOPs). GL-ALI-LEOPs exhibited excellent antibacterial and antioxidant properties and a sensitive, reversible, and rapid response to pH/NH3. Benefiting from good mechanical properties, light barrier properties and hydrophobicity of modified gelatin-based films, GL-ALI-LEOPs are readily processed into food packaging bags and smart tags. GL-ALI-LEOPs were successfully employed as an eco-friendly, low-cost, bacteriostatic and pH/NH3 quick-responsive smart trademark for real-timely monitoring and maintaining the freshness of shrimp.