The global turn from the linear to the circular economy imposes changes in common activities such as food packaging. The use of biodegradable materials such as polyvinyl alcohol, natural raw materials such as clays, and food byproducts such as chitosan to develop novel food packaging films attracts the interest of industrial and institutional research centers. In this study, novel hybrid nanostructures were synthesized via the growth of zinc oxide nanorods on the surface of two nanoclays. The obtained nanostructures were incorporated with chitosan/polyvinyl alcohol composite either as nanoreinforcement or as an active agent to develop packaging films. The developed films were characterized via XRD, FTIR, mechanical, water-vapor diffusion, water sorption, and oxygen permeability measurements. Antimicrobial activity measurements were carried out against four different pathogen microorganisms. XRD indicated the formation of an intercalated nanocomposite structure for both types of nanoclays. Furthermore, improved tensile, water/oxygen barrier, and antimicrobial properties were recorded for all films compared to the pure chitosan/polyvinyl alcohol film. Overall, the results indicated that the use of the bio-based developed films led to an extension of food shelf life and could be used as novel active food packaging materials. Among them, the most promising film was the 6% wt. ZnO@halloysite.
Three-dimensional (3D) printing has gained increasing attention for its unique ability to create geometrically complex designs, which not only can be used for mass manufacturing but also has environmental and economic benefits. Additionally, as far as the food industry is concerned, this emerging technology has the potential to personalize products in terms of shape and/or nutritional requirements creating a wide range of food items with specially made shapes, colors, textures, tastes, and even nutrition using suitable raw materials/food components. In the future, 3D food printing could make complex food models with special interior design. This review gives attention to intelligent food packaging. Point-of-use machinery for manufacturing smart packaging, with a 3D printing approach, enables the use of multifunctional smart components and is self-identifying and highly sensitive, while using biocompatible non-toxic materials is cheaper than traditional manufacturing methods. This would create smart food packaging and in turn prevent customers from purchasing unsuitable food and thus reduce food waste. Future studies can make the process more compatible and efficient with a wide variety of materials that could be used to improve the 3D printing process.