Submitted to: Journal of Association of Official Analytical Chemists International
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: November 1, 2009
Publication Date: January 5, 2010
Citation: Ricardi, J., Haavig, D., Cruz, L., Paoli, G., Gehring, A.G. 2010. Evaluation of the MIT RMID 1000 system for the identification of Listeria species:AOAC performance tested method 090325. Journal of Association of Official Analytical Chemists International. 93(1):249-258. Interpretive Summary: Rapid and inexpensive methods for the identification of harmful bacteria (pathogens) are required for food producers and regulatory agencies. Presently, the preferred methods for the identification of foodborne pathogens require extensive microbiological and biochemical testing that often take several days to complete. ARS scientists are working with Micro Imaging Technology (MIT) to develop methods to use their Rapid Microbial Identification (RMID) System for the very rapid (5-10 minutes) and inexpensive (~$0.50/test) identification of foodborne pathogens. Here we describe the successful testing of the MIT RMID System for identification of Listeria, including the deadly foodborne pathogen Listeria monocytogenes. The use of this system by food producers and regulatory agencies for the rapid identification of Listeria and other foodborne pathogens could safeguard consumers by reducing the burden of foodborne illness through a reduction in the distribution of contaminated foods.
Technical Abstract: The MIT 1000 RMID System is a rapid microbial identification device that uses the principles of light scattering coupled with proprietary algorithms to identify bacteria after being cultured and placed in a vial of filtered water. This specific method is for pure culture identification of Listeria spp. A total of 81 microorganisms (55 isolates) were tested by the MIT 1000 System of which 25 were Listeria spp. and 30 were a variety of other bacterial species. In addition, a total of 406 tests over seven different ruggedness parameters were tested by the MIT 1000 System to determine its flexibility to the specifications stated in the MIT 1000 System User Guide in areas where, in the Company’s view, might be deviated by a User to shorten the test cycle. Overall, Micro Imaging Technology (MIT) concluded that the MIT 1000 System had an accuracy performance that should certify this Performance Test Method (PTM) for the identification of Listeria spp. This report discusses the tests performed, results achieved and conclusions along with several reference documents to enable a higher understanding of the technology employed by the MIT 1000 System.