AOAC-RI ERP Micro June 2016

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

matrices tested in the study are shown in Table 2. The limit of detection of the 3M Molecular Detection Assay 2 – Listeria monocytogenes method is 1-5 colony forming

1 2 3

units per validated test portion size (in Table 2).

4 Table 2. Enrichment protocols using Demi-Fraser Broth at 37 ± 1 °C according to AOAC 5 Performance Tested SM Certificate #081501.

6 7

Enrichment Broth Volume (mL)

Enrichment Time (hr)

Sample Matrix

Sample Size

Beef hot dogs, Queso Fresco, Vanilla Ice Cream, 4% Milk Fat Cottage Cheese, 3% chocolate whole milk, romaine lettuce, bagged raw spinach, cold smoked salmon

25 g

225

24-30

Raw chicken

25 g

475

28-32

Deli turkey

125 g

1125

24-30

Enough volume to allow melon to float

Whole melon

Cantaloupe

26-30

Stainless steel Sealed concrete

1 sponge

225

24-30

1 sponge

100

24-30

Environmental samples:

Plastic

1 swab

10

24-30

8 F. P REPARATION OF THE 3M™M OLECULAR D ETECTION H EAT B LOCK I NSERT 9 Place the 3M™ Molecular Detection Heat Block Insert in a dry double block heater unit. Turn on the dry block heater unit and set the temperature to allow the 3M Molecular Detection Heat Block Insert to reach and maintain a temperature of 100 ±1°C. NOTE: Depending on the heater unit, allow approximately 30minutes for the 3M Molecular Detection 13 Heat Block Insert to reach temperature. Using an appropriate, calibrated thermometer (e.g., a partial 14 immersion thermometer, digital thermocouple thermometer, not a total immersion thermometer) placed in 15 the designated location, verify that the 3M Molecular Detection Heat Block Insert is at 100 ±1°C. 16 G. P REPARATION OF THE 3MM OLECULAR D ETECTION I NSTRUMENT 17 1. Launch the 3M™ Molecular Detection Software and log in. 18 2. Turn on the 3M Molecular Detection Instrument. 19 AOAC Research Institute Expert Review Panel Use Only 10 11 12

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