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3M MDA 2
Listeria
species and
L. monocytogenes
Collaborative Study
OMA-2016-MONTH-XXX
5/4/16
Note condition of package on the data sheets and notify the Study Director if any packages
1
appear to have been compromised or if the food product does not arrive in the appropriate
2
condition. All refrigerated products should arrive cold to the touch and should be stored at 2-8
°
C
3
(refrigerated) until the day of analysis.
4
5
Test Portion Analysis
6
7
Collaborators will be provided with enough sample to test each matrix using the 3M MDA2
8
methods and the appropriate reference method. For raw chicken breast, collaborators will
9
receive approximately 60g. One test portion (25g) will be weighed and tested using the 3M
10
MDA2 -
Listeria
and 3M MDA2 -
Listeria monocytogenes
and the other test portion (25g) will be
11
weighed and tested using the reference method. For deli turkey they will receive two sets of test
12
portions: 36 x 125g (3M MDA 2 -
Listeria monocytogenes
and 3M MDA 2 -
Listeria
) and 36 x
13
125g (USDA/FSIS MLG), for a total of 72 test portions. Please review the reference methods
14
carefully before initiating analysis.
15
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One additional 60 g control (negative) test portion will be provided to each collaborator for each
17
matrix to determine the total plate count on the day of analysis using the 3M™ Petrifilm™
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Aerobic Count Plate method (OMA 990.12). One temperature control sample will also be
19
included in the shipment to document the temperature of the sample upon receipt. Record all
20
results on the data sheets provided.
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Food Type
Reference
Reference
Pre-enrichment
3M MDA2
Enrichment
3M MDA2
Test Kit
Deli turkey
USDA/FSIS
MLG 8.09
UVM
Demi Fraser
Broth with
FAC
Listeria
&
L.
monocytogenes
Raw chicken
breast
USDA/FSIS
MLG 8.09
UVM
Demi Fraser
Broth with
FAC
Listeria
&
L.
monocytogenes
*Tryptone Soya Broth with yeast plus acriflavine (9 mg/L), nalidixic acid (36 mg/L) and cycloheximide
23
(46 mg/L)
24
25
Deli turkey
– use stomacher bag with filter for all 3M test portions.
26
27
1.0
3M MDA2 -
Listeria monocytogenes
and MDA2 -
Listeria
28
1.1
To each 125g test portion, add 1125 mL Demi Fraser broth without ferric
29
ammonium citrate (FAC). Homogenize each sample for two minutes ± 30 seconds
30
and incubate 24-30 h at 37 ± 1°C.
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1.2
Prepare the 3M MDS speed loader tray, chill block insert, heat block insert and
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instrument following the 3M MDA 2 -
Listeria monocytogenes
Instructions for
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Use [IFU] and 3M Molecular Detection Instrument manual.
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1.3
Equilibrate the LS tubes to room temperature (20-25 ºC) by setting LS tube
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overnight 16-18 hours. Or on the laboratory bench for at least 2 hours.
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1.4
Invert the capped LS tubes to mix, up to 4 hours before use.
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1.5
Transfer 20 µL enriched sample into a LS tube.
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AOAC Research Institute
Expert Review Panel Use Only
OMAMAN-29/OMAMAN-30 Combined Collaborative Study Protocol
OMA ERP - June 2016
ERP Use Only