Innovations in Biopolymer‐Based Anti‐Fog Food Packaging: From Surface Engineering to Sustainable Food Preservation

Anti-fog food packaging is defined as packaging that has undergone surface modification (e.g., superhydrophobic or superhydrophilic coatings) or is composed of special materials, the primary function of which is to regulate the wettability of the packaging in order to prevent condensation of water droplets on the inner surface of the package under specific conditions and the formation of fog. Conventional petroleum-based food packaging materials not only cause environmental pollution but also experience fogging issues, which compromise food safety and quality. Although bio-based materials are environmentally friendly, their anti-fogging performance requires further enhancement to suppress microbial growth and maintain packaging transparency without water condensation. This review explores anti-fogging mechanisms (superhydrophobic/superoleophilic strategies), fabrication techniques (chemical grafting, cross-linking, and additive assembly), and applications of bio-based packaging materials, highlighting the integration of multifunctional features (antimicrobial, antioxidant) and surface modifications to control wettability, gas permeability, and humidity stability for food preservation. Superhydrophobic (WCA ≥150°) and superhydrophobic (WCA ≈0°) materials effectively prevent fogging on packaging surfaces through rolling and spreading mechanisms. Additionally, chemical and physical modifications enhance durability and multifunctionality. Anti-fogging packaging reduces moisture condensation; inhibits microbial growth; and extends the shelf life of fruits, vegetables, and perishable foods. Future research should prioritize material durability, cost-effective scaling, and smart responsive design (e.g., pH and temperature-sensitive coatings) to develop sustainable food packaging solutions.