104 / 596
8
1
WARNING: Should you select to use Neutralizing Buffer (NB) that contains aryl
2
sulfonate complex as the hydrating solution for the sponge, it is required to perform a
3
1:2 dilution (1-part sample into 1-part sterile enrichment broth) of the enriched
4
environmental sample before testing in order to reduce the risks associated with a
5
false-negative result leading to the release of contaminated product. Another option is
6
to transfer 10 µL of the NB enrichment in the LS tubes.
7
8
(e)
The recommended size of the sampling area to verify the presence or absence of the
9
pathogen on the surface is at least 100 cm
2
(10 cm x 10 cm or 4”x4”). When sampling
10
with a sponge, cover the entire area going in two directions (left to right then up and
11
down) or collect environmental samples following your current sampling protocol or
12
according to the FDA BAM, USDA FSIS MLG or ISO 18593 [11] guidelines.
13
1.
Allow the Demi-Fraser Broth enrichment medium (includes ferric ammonium
14
citrate) to equilibrate to ambient laboratory temperature (20-25
o
C).
15
2.
Aseptically combine the enrichment medium and sample according to Table 2.
16
3.
Homogenize thoroughly by blending, stomaching, or hand mixing for 2 ±0.2
17
minutes. Incubate at 37 ±1°C for 24-30 hours.
18
19
E.
P
REPARATION OF THE
3M™M
OLECULAR
D
ETECTION
S
PEED
L
OADER
T
RAY
20
(a)
Wet a cloth or paper towel with a 1-5% (v:v in water) household bleach solution and
21
wipe the 3M™ Molecular Detection Speed Loader Tray.
22
(b)
Rinse the 3M Molecular Detection Speed Loader Tray with water.
23
(c)
Use a disposable towel to wipe the 3M Molecular Detection Speed Loader Tray dry.
24
(d)
Ensure the 3M Molecular Detection Speed Loader Tray is dry before use
25
26
Specific Instructions for Validated Methods
27
AOAC® Performance Tested Method
SM
#111501
28
29
30
31
In AOAC PTM studies, the 3M Molecular Detection Assay 2 –
Listeria
was found to be an
32
effective method for the detection of
Listeria
species
.
The matrices tested in the study are
33
shown in Table 2. The limit of detection of the 3M Molecular Detection Assay 2 –
Listeria
34
method is 1-5 colony forming units per validated test portion size (in Table 2).
35
AOAC R search Institute
Expert Review Panel Use Only
OMAMAN-29 A/ Collaboartive Study Manuscript
OMA ERP June 2016
ERP Use Only