Titanium dioxide (TiO2) for the manufacture of multifunctional active food packaging films

Due to environmental issues caused by plastic packaging and increasing consumer demand for fresh and safe food, there is increasing interest in developing active food packaging films containing metal nanoparticles. Titanium dioxide (TiO2) is a metal oxide nanoparticle with low toxicity, economy, and stability. It is recognized as a functional nano-filler for biodegradable food packaging films due to its excellent biocompatibility, photocatalysis, and antibacterial properties. The advantages and challenges of adding TiO2 to active food packaging film properties such as thickness, moisture sensitivity, moisture barrier properties, color, light barrier properties, mechanical properties, antibacterial and photocatalytic properties were discussed. Besides, the practical application and migration properties of TiO2 in the active films for food packaging applications were also discussed. The addition of TiO2 can impart antimicrobial properties to the active film and act as a crosslinking agent to improve other physical and chemical properties of the film, such as mechanical and barrier properties. The application of TiO2 can also impart ethylene scavenging activity to the active film, which is essential to extend the shelf life of fruits after harvest. The negligible migration of TiO2 from the composite film to food makes it safe for use in food packaging applications.