Titanium dioxide (TiO 2 ) photocatalysis technology for nonthermal inactivation of microorganisms in foods

Abstract Background Microbial contamination is a serious challenge in the food industry. With the increasing demand for fresh, nutritious and healthy food, novel techniques for microbial inactivation are highly needed. By absorbing photoenergy, titanium dioxide (TiO2) based photocatalyst can produce reactive oxygen species (ROS) that are capable of inactivating microorganisms. Scope and approach This review summarizes recent research developments of TiO2 photocatalysis (TPC) for antibacterial applications in liquid, gas and solid systems in the food industry. Basic principles of TPC, the mechanism of photocatalytic inactivation, and strategies for improving photoactivity are described, and applications of TPC for decomposing organic substances are presented. Furthermore, applications of combining TPC with other technologies are also discussed. Conclusions and key findings: The review shows that TPC technology has the ability to inactivate foodborne microorganisms, but with some drawbacks such as catalyst deactivation and low utilization of visible light. Modification can widen the light response into visible range and improve the photoactivity. The combined technologies can enhance the effectiveness of microbial inactivation. However, further study is still needed to improve both photocatalytic disinfection efficiency and food quality maintenance.