Novel photodynamic antimicrobial films loaded with Chinese artichoke carbon dots for chilled mutton preservation

Meats spoilage caused by microbial contamination leads to significant resource wastage. Photodynamic inactivation is emerging promise as an antimicrobial strategy due to the generation of reactive oxygen species (ROS) through photosensitizers. Here, carbon dots (CA-CDs) prepared from Chinese artichoke (CA) as precursor were introduced into poly(vinyl alcohol) (PVA) to construct photodynamic antimicrobial films with enhanced freshness retention properties. The synthesized CA-CDs display homogeneous and monodisperse spherical structure with ultra-small size, facilitating uniform films formation. Encouragingly, the CA-CDs remarkably improve the UV shielding, antioxidant properties of PVA films, with the PVA/CA-CD5 and PVA/CA-CD10 compositions (blended with 5 and 10 mL of CA-CDs, respectively) demonstrating superior packaging performance. Furthermore, these films exhibit excellent ROS generation capabilities and antimicrobial activity. Finally, the PVA/CA-CD5 and PVA/CA-CD10 are used to preserve chilled mutton, resulting in a corresponding extension of storage life by 6 days. These findings highlight a novel strategy for preservation of chilled mutton.