Functional Feature Improvement of the Banana Leaf‐Based Traditional Packaging Through Propolis and Zinc Oxide Nanoparticle Coating

ABSTRACT Banana leaf‐based packaging has been widely used for various traditional foods in Indonesia, contributing to the aesthetics and enhancing the aroma, color, flavor, and ethnic appeal. The inherent properties of banana leaves are insufficient to prevent the growth of microorganisms, leading to spoilage of the wrapped food. The objective of this study was to introduce the cultural practice of using banana leaves as traditional food packaging in Indonesia and to enhance their biofunctional properties through the application of a coating technique using propolis and zinc oxide nanoparticles (ZnONP). At least 17 traditional lexicalization patterns of banana leaf‐based packaging were identified across Indonesia. A nanocomposite formulation of 3% propolis combined with 140 ppm ZnONP was selected for coating. The prepared banana leaf thickness and color difference ranged from 0.262 to 0.264 mm and 76.64–86.09, respectively, with the coating layer being observed on the surface and within the internal microstructure through scanning electron microscopy (SEM). The combination of propolis and ZnONP exhibited the highest antimicrobial activity against both Gram‐positive and Gram‐negative bacteria, as demonstrated by the inhibition of Bacillus subtilis and Escherichia coli . The coated banana leaf traditional packaging extended the shelf life of lemper (a traditional Indonesian food) by 8–12 h.