Tea Polyphenol Self-Assembly Nanocomposite Coating for Fruit Preservation

Fruit spoilage has led to significant food waste and economic losses and poses risks to human health. Currently, widely used plastic bag preservation techniques exhibit limited effectiveness, often leading to environmental pollution and potential health hazards. Moreover, many emerging nanopreservation materials lack comprehensive safety evaluations, raising concerns regarding their biological safety and stability. In this study, we developed a nanocomposite coating that utilizes plant-derived polyphenols as a structural framework for food preservation. This coating is synthesized through a one-step self-assembly process involving tea polyphenols and zinc ions (TPZn). The TPZn nanocomposite coating exhibits exceptional antibacterial, antioxidant, adhesion, and water retention properties. By inhibiting the formation of bacterial biofilms, it effectively prevents bacteria from colonizing the surfaces of fruits, resulting in long-lasting antibacterial effects and significantly extending the shelf life. Additionally, the application of TPZn on strawberries and bananas has led to a doubling of their shelf life while maintaining the freshness and nutrient content of the fruits. This polyphenol-based preservation material not only provides a shield coating against spoilage but also demonstrates excellent biological safety across various models including cells, zebrafish, nematodes, mice, and bean sprouts. This study presents insights into the rational design of biosafe preservation materials utilizing natural plant-derived components.