Zein-Based Packaging and Coating Materials for Postharvest Preservation of Fruits and Vegetables: Modification Strategies and Mechanistic Insights.

Abstract

Postharvest losses of fruits and vegetables remain a critical constraint to global food security, necessitating sustainable preservation strategies. This review critically examines recent advances in zein-based materials for postharvest applications, with emphasis on preservation performance and functional optimization. Zein-based edible coatings and composite films have demonstrated significant reductions in moisture loss and microbial spoilage by forming semi-permeable matrices with low water vapor and oxygen permeability, thereby effectively extending the shelf life of high-respiration produce. Advance architectures including electrospun nanofibers and multilayer systems, further enhanced barrier efficiency and enabled antimicrobial functionality. In addition, nanostructured zein carriers facilitated controlled release of bioactive compounds, improving preservation outcomes in fruits such as strawberries, bananas, and mangoes. However, while zein exhibits favorable moisture barrier properties in the solid state, its inherent hydrophobicity and limited aqueous processability pose challenges during formulation and large-scale production. Mechanical brittleness and sensitivity to high-humidity storage conditions further restrict standalone application. Current research therefore focuses on composite engineering, green plasticization, and scalable fabrication strategies to overcome these limitations. Addressing these processing and stability constraints is essential to accelerate industrial translation of zein-based systems as sustainable alternatives to petroleum-derived postharvest packaging materials.