Improving food safety by eliminating pathogens in mixed biofilms

Abstract

Food safety is of worldwide importance and despite efforts to reduce foodborne illnesses, both well-known and emerging pathogens are frequently involved in disease outbreaks that greatly impact public health and food processors. Brazil and Denmark are important producers and exporters of food commodities and ensuring microbial safety of food is a key challenge to both Brazilian and Danish food processors and scientists. The purpose of this project is to reduce the risk of pathogen contamination during food processing from farm to fork, especially in dairy plants. We will target the natural mixed microbial biofilms harboring bacterial pathogens that can reach foods during processing and thus be transferred to the consumer especially in ready to eat foods. Our rationale is that targeting non-pathogenic microbiota associated with pathogens is a key issue to be able to effectively design cleaning and disinfection procedures since the mixed microbial biofilm protects the pathogen. Also, in our model systems we will use natural food soil to mimic the actual conditions at plant level. We will survey and describe the autochthonous microbiota in at least three dairy processing plants and determine possible correlations with key pathogens Listeria monocytogenes and Staphylococcus aureus in these environments. We will determine how the natural mixed microbiota and soil influences pathogen reduction during disinfection and we will address the potential influence of the commensals on virulence properties of the pathogens to target high risk niches. We will use a range of both classical and state-of-the art microbiological methods in our work, ranging from agar plating, to PFGE subtyping and genome sequencing. Finally, we will recommend optimised cleaning and disinfection procedures to food processing plants. (AU)