AOAC-RI ERP Micro June 2016

OMAMAN-30 A/ Collaborative Study Manuscript OMA ERP June 2016 ERP Use Only

Environmental samples

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(d) Sample collection devices can be a sponge hydrated with a neutralizing solution to inactivate the effects of the sanitizers. 3M recommends the use of a biocide-free cellulose sponge. Neutralizing solution can be Dey-Engley (D/E) Neutralizing Broth or Letheen broth. It is recommended to sanitize the area after sampling. WARNING: Should you select to use Neutralizing Buffer (NB) that contains aryl sulfonate complex as the hydrating solution for the sponge, it is required to perform a 1:2 dilution (1-part sample into 1-part sterile enrichment broth) of the enriched environmental sample before testing in order to reduce the risks associated with a false-negative result leading to the release of contaminated product. Another option is (e) The recommended size of the sampling area to verify the presence or absence of the pathogen on the surface is at least 100 cm 2 (10 cm x 10 cm or 4”x4”). When sampling with a sponge, cover the entire area going in two directions (left to right then up and down) or collect environmental samples following your current sampling protocol or according to the FDA BAM, USDA FSIS MLG or ISO 18593 [11] guidelines. 1. Allow the Demi-Fraser Broth enrichment medium (includes ferric ammonium citrate) to equilibrate to ambient laboratory temperature (20-25 o C). 2. Aseptically combine the enrichment medium and sample according to Table 2. 3. Homogenize thoroughly by blending, stomaching, or hand mixing for 2 ±0.2 to transfer 10 µL of the NB enrichment in the LS tubes.

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minutes. Incubate at 37 ±1°C for 24-30hours. 23 24 E. P REPARATION OF THE 3M™M OLECULAR D ETECTION S PEED L OADER T RAY 25

(a) Wet a cloth or paper towel with a 1-5% (v:v in water) household bleach solution and wipe the 3M™ Molecular Detection Speed Loader Tray. (b) Rinse the 3M Molecular Detection Speed Loader Tray with water. (c) Use a disposable towel to wipe the 3M Molecular Detection Speed Loader Tray dry. (d) Ensure the 3M Molecular Detection Speed Loader Tray is dry before use

AOAC Research Institute Expert R view Panel Use Only

Specific Instructions for Validated Methods AOAC® Performance Tested Method sm # 081501

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In AOAC PTM studies, the 3M Molecular Detection Assay 2 – Listeria monocytogenes was found to be an effective method for the detection of Listeria monocytogenes. The

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