Recent advances in nano-reinforced food packaging based on biodegradable polymers using layer-by-layer assembly: A review

Multilayer food packaging has gained popularity due to its versatility, functionality, and convenience. There are numerous methods for producing multilayer nano-reinforced food packaging, such as coextrusion, casting, spinning, and layer-by-layer (LBL) technologies. LBL technique is one of the easiest, most flexible, efficacious, and economical method for fabricating nanoscale multilayer composite films with accurate control of structure, diameter, and qualities. This is a suitable technology to improve the barrier, mechanical, and functional properties of biodegradable/compostable polymers, produced using carbohydrates, proteins, polylactic acid, etc. for food packaging purposes. This review aims to show an overview of promising ordinary LBL assembly methods used for biobased food packaging, such as LBL by immersion, spray, spinning, casting, as well as the possibility of combining LBL methods, namely spinning-spray assisted. LBL methods are also discussed in terms of their mechanism of action and potential applications. The current literature indicates that LBL methods decrease the permeability rate of water vapor molecules and gases, reduce microbiological growth, and improve the mechanical performance of multilayer biobased food packaging. Further studies should continue to focus on minimizing the potential hazards of nano-reinforced food packaging produced by LBL assembly, including toxicity and environmental concerns, decreasing production costs, and producing nano-reinforced multilayer food packaging at industrial scale.