Microbiology Methods for ERP Review 3-2020

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1.0 1 2 The purpose of this collaborative study is to determine the performance of the candidate method 3 among collaborators for the detection of Salmonella . Estimates of repeatability, reproducibility and 4 probability of detection (POD) will be evaluated. Collaborators will analyze one matrix at 3 5 contamination levels comparing the performance of the candidate method to appropriate reference 6 culture method. The Solus One Salmonella is the candidate method. The U.S. Food and Drug 7 Administration Bacteriological Analytical Manual (FDA BAM) Chapter 5 (1) is the reference method for 8 this study. 9 10 1.1 Solus One Salmonella Introduction The Solus One Salmonella method is an enzyme ‐ linked immunosorbent assay (ELISA) designed to detect Salmonella ( Salmonella enterica subspecies enterica , salamae , arizonae , diarizonae , houtenae , indica and Salmonella bongori ) in select foods and environmental samples following enrichment containing a proprietary supplement. The method utilizes antibodies bound to the wells of microplate strips that are specific to Salmonella antigens and detects both motile and non ‐ motile Salmonella . Heat inactivated/lysed samples are added to the wells of the plate and sample analysis is conducted following a manual or a fully automated protocol on the Dynex DS2 instrument. Results are based on optical density levels resulting from a color change reaction in the wells. Presumptive positive or negative results can be obtained in as little as 22 h for most

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food samples and 18 h for environmental samples. See Attachments 1 and 2.

1.2

Summary of the Performance Tested Method SM Validation

The Solus One Salmonella method was certified by the AOAC Research Institute in October, 2018 and designated Performance Tested Method SM (PTM) 101801 for six food matrices; raw beef trim (375 g), instant non ‐ fat dry milk powder (NFDM, 375 g), pasteurized liquid egg (100 g), raw salmon (25 g), cheddar cheese (25 g), Romaine lettuce (25 g), and two environmental surfaces (stainless steel and polystyrene). A method modification was approved in August 2019 to include herbs, spices and flavorings; whole black peppercorns, paprika powder and cinnamon powder (25 g sample size) plus honey mustard onion seasoning and flavored ranch seasoning

(375 g sample size). See Attachments 3 and 4.

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Study Directors

Ray Wakefield

Solus Scientific Solutions, Ltd.

9 Mansfield Networkcentre, Millennium Business Park

Concorde Way, Mansfield

Nottinghamshire NG19 7JZ, United Kingdom Email: ray.wakefield@solusscientific.com

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