71 / 453
7
and reagent tubes after amplification. Dispose of enriched samples according to current industry
1
standards.
2
To reduce the risks associated with environmental contamination:Follow current industry standards for
3
disposal of contaminated waste.
4
D.
Sample Enrichment
5
6
Foods
7
(a)
Allow BPW ISO enrichment medium to pre-warm to 41.5±1°C. See Table A for matrix-specific
8
enrichment protocols.
9
(b)
Aseptically combine the enrichment medium and sample. For all meat and highly particulate samples,
0
the use of filter bags is recommended.
1
(c)
Homogenize by stomacher, hand, or gentle agitation thoroughly for 2 ± 0.2 minutes. Incubate matrices
2
according to the instructions provided in Table A.
3
4
E.
P
REPARATION OF THE
3M™M
OLECULAR
D
ETECTION
S
PEED
L
OADER
T
RAY
5
(a)
Wet a cloth or paper towel with a 1-5% (v:v in water) household bleach solution and wipe the 3M™
6
Molecular Detection Speed Loader Tray.
7
(b)
Rinse the 3M Molecular Detection Speed Loader Tray with water.
8
(c)
Use a disposable towel to wipe the 3M Molecular Detection Speed Loader Tray dry.
9
(d)
Ensure the 3M Molecular Detection Speed Loader Tray is dry before use
0
1
2
Table A. 3M MDA 2 –
E. coli
O157 (including H7)enrichment protocolsusing pre-warmed BPW ISO
3
at 41.5 ± 1°Caccording to AOAC
Official Method
SM
2016.XX4
Sample Matrix
Sample Size
Enrichment Broth Volume
Enrichment Time
(hour)
Homogenized
Raw ground beef (73% lean)
325 g
975 mL
10-18
Manually by
hand
Raw bagged spinach(a)
200 g
450 mL
18-24
Gently agitated
by hand for 5
minutes
Fresh sprouts
25 g
225 mL
18-24
Stomach
Frozen blueberries(a)(b)
25 g
225 mL
18-24
Gently agitated
by hand for 5
minutes
(a) Leafy produce and fruit samples should be gently agitated by hand for 5 minutes. Do not blend or stomach.
5
(b) Frozen samples should be equilibrated to 4-8°C before addition to enrichment broth.
6
7
8
9
F.P
REPARATION OF THE
3M™M
OLECULAR
D
ETECTION
C
HILL
B
LOCK
I
NSERT
0
OMAMAN-35 A : Collaborative Study Manuscript
For ERP Use Only
January 2017
AOAC Research Institute
Expert Review Panel Use O ly