Biomimetic Design of Biopolymer-Based Water-Resistant Food Packaging Materials.

With the growing demand for sustainable and eco-friendly food packaging, biopolymer-based materials are emerging as promising candidates due to their recyclability, biodegradability, and food safety. However, in practical applications dealing with high moisture content or perishable foods, their lack of water resistance poses a significant barrier, limiting their widespread use. This review comprehensively summarizes recent advances in biomimetic strategies to overcome these limitations of biopolymer-based packaging, focusing specifically on water resistance and hydrophobic biopolymer-based packaging systems. Inspired by natural surfaces, such as lotus leaves, mussel adhesive layers, insect cuticles, and nacre, researchers have developed functional films through nanocomposite reinforcement, hierarchical surface structuring, and chemical or biomimetic surface modification. It further provides an in-depth discussion of fabrication techniques, structure-function relationships, and real-world food applications, including fruits, vegetables, meat, seafood, bakery products, and liquid foods. It also highlights current challenges in scalability, biodegradability, and reproducibility, while introducing new tools, such as advanced characterization and machine learning, to accelerate innovation. Focusing specifically on water resistance, a crucial performance indicator, this review offers insights into developing robust, sustainable, and functional food packaging systems that can replace petroleum-based plastics. Key findings suggest that nature-inspired designs significantly improve water repellency without compromising biodegradability. Looking forward, bioinspired biopolymer systems hold strong potential to reshape future food packaging by aligning environmental safety with practical performance.