Dual-function photosensitive bacterial cellulose film for real-time meat freshness monitoring and rapid sterilization

Microbial contamination leading to food spoilage necessitates the development of food packaging films with both monitoring and sterilization functions. In this study, we developed a dual-functional film named Anthocyanin/Alizarin-hypocrellin B (ATH/ALI-HB) that simultaneously integrates freshness monitoring, sterilization, and data-driven freshness evaluation within a single platform. By integrating bacterial cellulose with polysaccharides, the ATH/ALI-HB film substrate effectively overcomes the intrinsic brittleness of pure bacterial cellulose films. Incorporating various pigments, the film exhibits sensitive pH-dependent color changes for freshness monitoring. Specifically, the ATH/ALI-HB film's change from brown to purple signals the onset of the spoilage process, and it successfully delays meat spoilage until day 10. Photosensitizers incorporated into the film improve sterilization efficiency, as demonstrated by the ATH/ALI-HB film's ability to reduce Listeria monocytogenes populations from 10 6  CFU/mL within 15 min due to the production of reactive oxygen species (ROS). Additionally, a one-dimensional convolutional neural network (1D-CNN) model based on Raman spectrum was proposed to make a more precise judgment of the freshness of meat, enabling fully accurate (100%) classification of meat freshness states. This work presents a novel strategy for intelligent food packaging, in which material design, monitoring, sterilization, and artificial intelligence–assisted sensing are seamlessly integrated, paving the way for future advancements in food packaging technology.