AOAC-RI ERP Micro June 2016

OMAMAN-29 A/ Collaboartive Study Manuscript OMA ERP June 2016 ERP Use Only

Overall, the data generated during this evaluation demonstrates the reproducibility of this new 1 method. For the deli turkey analysis, the POD statistical analysis indicated thatno statistically 2 significant difference between the candidate method and the reference method or between the 3 presumptive and confirmed results of the candidate method was obtained. For raw chicken breast 4 fillet, a statistically significant difference was observed between the reference and the alternative 5 method. The dLPOD data indicated a positive correlation in data indicating more recovery of the 6 target analyte by the candidate method. One possible contribution to the higher level of recovery 7 observed with the 3M MDA 2 – Listeria method was the use of Demi-Fraser Broth for the 8 candidate method. This enrichment media formulation is less selective than the modified 9 University of Vermont Medium used in the USDA reference method and may have contributed 10 to the higher level of recovery observed during the evaluation. A second possible contribution to 11 the higher level of recovery was the length of the primary enrichment. Test portions evaluated 12 by the 3M MDA 2 – Listeria method were incubated for a minimum of 28 hours in the primary 13 enrichment, while the USDA reference method had a maximum primary enrichment time of 26 14 hours. No statistically significant difference was observed between the candidate method 15 presumptive and confirmed results for this matrix. 18 19 It is recommended that the 3M Molecular Detection Assay 2 – Listeria method be adopted as 20 Official First Action status for the detection of Listeria in selected foods: hot dogs (25g & 125g), 21 salmon (25g), deli turkey (25g & 125g), cottage cheese (25g), vanilla ice cream (25g), queso 22 fresco (25g), spinach (25g), melon (whole), raw chicken leg pieces (25g), raw chicken fillet 23 (25g); concrete, stainless steel and plastic environmental samples. 26 27 We would like to extend a sincere thank you to the following collaborators for their dedicated 28 participation in this study: 29 30 Robert Brooks- ATC Microbiology, LLC- North Little Rock, AR. 31 Jaspreet Walia & Francisco Hernandez – Certified Laboratories, Turlock, CA 32 David Bosco& Grizelda Trevino– Food Safety Net Services, Fresno, CA 33 Alex Brandt & Chris Lopez – Food safety Net Services, San Antonio, TX 34 Elizabeth Sjogren&Manish Shekhawat– Microbac Laboratories, Inc. Worcester, MA 35 Li Maria Ma, Chris Timmons, & Claudia Diaz Proano – Oklahoma St. University, Stillwater, 36 OK 37 Alexandra Calle & David Campos – Texas Tech University, Lubbock, TX. 38 Zachary Metz&David Baumler, University of Minnesota, St. Paul, MN 39 Robbie Smith, Dianne Wood, Evelyn Maranan,&Carmen Chavarria Maple Leaf Foods– Guelph, 40 ON, Canada 41 Ben Bastin– Microbiology R&D, Q Laboratories Inc., Cincinnati, OH 42 David Isfort– Microbiology-Food, Q Laboratories Inc., Cincinnati, OH 43 Jesse Miller, Bryan Schindler, Courtney Gies, Eric Budge, Zach Geurin & Alex Repeck - NSF 44 International, Ann Arbor, MI 45 Cynthia Zook & Christina Barnes – 3M Food Safety, St. Paul, MN 46 AOAC Research Institute 16 17 Recommendations 24 25 Acknowledgements

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