Airborne contamination in the food industry: An update on monitoring and disinfection techniques of air

Background hygienic and safe production is a high priority in the food industry. During processing, food may be subjected to bio-contamination. Accordingly, preservation of overall quality by keeping a clean environment is a goal to pursue. Among microbial vectors, air is considered a contributing factor to cross-contamination. Scope and approach: nowadays, in food plants emphasis is paid to the assessment of air bioload in view of prevention of recontamination. Normally, air entering a processing plant is chilled and filtered to remove undesired microorganisms from outside. Nevertheless, apart from clean-room environments, uncontrolled factors (processes, personnel, structures, etc.) contribute to the release of microorganisms in indoor environments, resulting in generation of bioaerosols highly variable within and among plants, and on a daily basis within the same plant. Key findings and conclusions: this review focuses on the relevance of bioaerosol monitoring in the food industry, providing an update of air sampling techniques and methods of analysis in view to strengthen preventive hygienic actions. Disinfection procedures to minimize microbial counts in the air as additional safeguard to the standard chemical sanitation protocols are reviewed. Benefits and limitations of air treatment by chemical fogging, ozonation, uv irradiation or cold plasma are outlined. Air bioload monitoring and the implementation of subsequent air disinfection procedures are a feasible and a routinely exploitable strategy to satisfy hygienic requirements in food plants. Further research is required to face technical challenges and optimize the feasibility of some disinfection technologies for the real-world of food environments.