Nanoporous Carriers for Active, Sustainable Food-Packaging Films and Coatings: A Cross-Platform Comparison and Design Rules

Active and sustainable food packaging increasingly relies on additives (antioxidants, antimicrobials, and gas or volatile scavengers) that extend shelf life and reduce food waste, yet delivering these functions from thin films and coatings without sacrificing processability, transparency, or food-contact safety remains a persistent engineering problem, and effectiveness is still commonly pursued by raising additive dosage. Nanoporous solids offer an alternative, because their tunable pores and high internal surface area allow actives to be stored on internal surfaces and metered through pore architecture and surface chemistry, decoupling function from dosage, while the same fillers can improve barrier performance through tortuosity and sorption. Because the literature has developed platform by platform, this review compares five families (zeolites, ordered mesoporous silica, halloysite nanotubes, metal–organic frameworks, and porous carbons) as additive carriers for flexible food-packaging films and coatings, linking pore architecture and surface chemistry to loading, release, scavenging, and barrier enhancement, and to scalable integration routes including melt compounding, solvent casting, and waterborne coating. Release-kinetic analysis and an order-of-magnitude ethylene mass balance indicate that affinity and access under realistic humidity, rather than nominal capacity, usually limit performance, and comparative benchmarking shows that no single platform dominates: zeolites and porous carbons rate highly on cost and processing robustness, metal–organic frameworks on loading and selectivity, and mesoporous silica and halloysite occupy a deployable middle ground. Future work should prioritize quantitative pore-transport design rules, one-filler multi-function systems, manufacturing-ready waterborne topcoats, and standardized migration testing tailored to nanoporous carriers.