Advancement of a multifunctional composite coating encapsulating CGA-Zn2+ MPN nanoparticles for enhanced postharvest fruit preservation

Fresh fruits and vegetables, rich in vitamins and essential nutrients, play an essential role in supporting human health. However, the perishability during transit and storage causes rapid degradation; consuming spoiled items poses significant health risks. Extending the shelf life of fresh produce has therefore become a key challenge for the food industry. In this study, a multifunctional composite coating was developed by integrating chlorogenic acid–zinc ion (CGA-Zn 2+ ) metal–phenolic network (MPN) particles into a polymer matrix composed of sesbania gum (SG) and biguanide-modified chitosan (Bi-Ch). Cherry tomatoes were used as the model fruit to investigate the coating's preservation effect. The CGA-Zn 2+ MPN particles provided strong antioxidant properties, which worked in combination with the antibacterial activity of Bi-Ch, enabling the coating to offer both protective and bioactive functions. The addition of MPN particles significantly improved the antioxidant capacity of the coating, increasing it from 64.83 % to 97.31 %. Moreover, the coating showed enhanced antibacterial performance. Preservation results confirmed that this composite coating effectively extended the shelf life of cherry tomatoes to 9 days at least while maintaining their quality. Cytocompatibility assays validated its safety for food applications. As a biocompatible, readily removable intervention, this approach offers considerable promise for enhancing fresh fruit stability throughout supply chains—mitigating waste and bolstering food safety.