Paper-Based Smart Packaging: Multifunctional Materials for Sustainable Food Preservation

Given the dual challenges of global food waste and plastic pollution, paper-based packaging has emerged as a sustainable alternative to petroleum-based plastics. However, native paper exhibits poor barrier performance and high hydrophilicity, restricting its direct application in food preservation. This review systematically summarizes recent advancements in multifunctional paper-based smart packaging. It highlights core modification strategies like internal additive incorporation, impregnation, coating, surface functionalization, and layer-by-layer assembly that evolve paper from passive protection to active regulation and intelligent sensing. Crucially, matrix-specific synergistic systems are discussed. For fresh produce, research focuses on respiration control via ethylene scavenging. For high-protein foods, emphasis shifts to robust oxygen barriers against lipid oxidation and real-time freshness monitoring. Furthermore, current challenges restricting industrial translation are critically analyzed, primarily the recyclability paradox of high-performance coatings, unpredictable migration safety, and the scalability gap. Future research must prioritize stimuli-responsive closed-loop systems and recycling-compatible barrier structures. Ultimately, this review presents perspectives on a design framework for balancing functional performance with fiber recyclability, with the aim of guiding future endeavors in the commercialization of sustainable smart packaging within a circular economy.