2007 Annual Report 1a.Objectives (from AD-416) The objective of this cooperative research project is to develop and optimize a product for use against Listeria monocytogenes biofilm in meat and poultry processing equipment and to develop standard methodologies for biofilm removal for registration of EPA biofilm claims for products used in food processing. 1b.Approach (from AD-416) Develop methods to produce biofilms for further study and for quantification of biofilms on surfaces including batch culture within a reactor. Establish baseline data of Sterilex technology against L. monocytogenes biofilms and mixed species biofilms containing L. monocytogenes under food processing plant conditions with AOAC use-dilution testing. Determine mechanism of action of current Sterilex technology in conjunction with chemical screening by total organic carbon analysis. Optimize product against multi-species biofilms in meat and poultry processing equipment and test final product with use-dilution test. 3.Progress Report This report documents research conducted under a trust agreement between ARS and Sterilex. Additional details of research can be found in the report for the in-house associated project 6612-32000-055-00D, Molecular Characterization and Gastrointestinal Tract Ecology of Commensal Human Foodborne Bacterial Pathogens in the Chicken. The focus for this year has been completion of baseline data established during the first year. Methods developed during the first year to produce Listeria monocytogenes biofilms and test Sterilex technology were used to complete chemical screening of potential product components for biofilm removal activity. New methods were implemented to screen for detection efficacy against L. monocytogenes biofilms, with concomitant testing of biofilm sustainability and bacterial cell culturability from the biofilms. Methods recommended by experts in the area of biofilm biology and our previous experiments with Campylobacter were not effective with Listeria. We have analyzed chemical screening data to optimize product formulations for selection of test components. After variance of the calcium sequestrants and nonionic surfactants in the formulations, we completed colorimetric measurement of dye staining and extractions of L. monocytogenes biofilm as the biofilm screening test agent. Field strains continued to be more susceptible to the chemistry than laboratory strains. We are ready to test the final product to meet USDA ‘zero tolerance’ regulations for L. monocytogenes biofilms, and its activity will be confirmed by the AOAC use-dilution test. Protocol development and validation is critical to the establishment of standards for registration of EPA biofilm claims for used in food processing. Such claims will educate end users about biofilms and the important of utilizing products that can address the problem of biofilms in food processing environments. Understanding the mechanism of action underlying the effectiveness of the current Sterilex technology is critical for the future development of effective products for use against biofilms containing Listeria monocytogenes and other harmful pathogens. The results of these experiments will yield an optimized formulation of a disinfectant for meat and poultry RTE food processing and production equipment that is more effective in reducing Listeria monocytogenes biofilm growth than currently used disinfectants, thus minimizing the risks to food safety from pathogenic contamination. During the past year, monitoring activities included weekly to bi-weekly conference calls and/or emails to review progress, data, and exchange technical advice. Review of project plans, program goals, and accomplishments were conducted off-site at a stakeholders meeting in July, 2007. The Cooperator’s annual progress report was presented in person to the granting agency at a celebration for NRI awardees, October, 2006; and to the ADO in writing, on schedule, as required, in December, 2006. A cumulative, detailed research report was submitted to the RL, Area Director, and granting agency, June 2007.