Microbiology Methods for ERP Review 3-2020

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AOAC Official Method 2020.XX Salmonella species in Select Foods Solus One Salmonella Assay First Action 2020

Applicable to detection of Salmonella in the following: 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), honey mustard season (375 g), flavored ranch seasoning (375 g), cinnamon powder (25 g), paprika powder (25 g) and whole black peppercorns (25 g) and two

environmental surfaces (stainless steel: sponges and polystyrene: swabs). See Tables 2020.01A for a summary of results of the inter-laboratory study. See Tables 2020.01B for detailed results of the inter-laboratory study A. Principle

The Solus One Salmonella immunoassay utilizes Salmonella specific selective media and can process samples either manually or using automated liquid handling (DS2), for the rapid and specific detection of Salmonella species in select food types. The alternative method was evaluated using 375 g test portions in an unpaired study design for a single matrix of instant NFDM powder. 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 sample enrichments 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. Solus Scientific Solutions Ltd., 9 Mansfield Network Centre, Millennium Business Park, Concorde Way, Mansfield, Nottinghamshire NG19 7JZ, UK a. 96 well microplates coated with antibodies against Salmonella species. b. Negative Control (Green Label) c. Positive Control (Red Label) d. Conjugate (Orange Label) e. Substrate (Blue Label) f. Stop Solution (Silver Label) g. Washing Buffer Concentrate (25x) h. Washing Buffer Activator i. Product Instructions (b) Dehydrated Buffered Peptone Water (BPW) Medium according to ISO 6579, CAT No. MED017. (c) Dehydrated Solus modified Buffered Peptone Water (Solus mBPW), CAT No. MED038. (d) Solus One Salmonella Supplement, CAT No. SALSUPP-22.5 & SALSUPP-112. (e) Dynex Technologies DS2 Instrument (Dynex DS2).—Dynex Technologies, Chantilly, VA. (f) Computer with DS2 Software. B. Apparatus and Reagents Items Available from Solus Scientific (Nottinghamshire, UK). (a) Solus One Salmonella – Solus, cat. SAL1-0480 & SAL1-0096

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