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3M MDA2 E. coli O157:H7 Collaborative Study
May 2016
OMA-2016-May-XXXX
DRAFT DOCUMENT
16
Appendix 8.4 – Flow Diagram for Raw Ground Beef (325g)
1
2
3M MDA2
USDA/FSIS MLG
3
4
Raw ground beef
325g + 975 mL BPW ISO
(prewarmed to 41.5C)
Pull aliquot after
10 hours to test
following the 3M
MDA2
E. coli
O157
(including H7)
assay
After 10 hr,
follow MLG
confirmation
steps
Antibody-based screening test
Perform IMS
Spread plate beads (diluted &
undiluted) to mRBA
incubate 20-24 hr at 35±2°C
*with and without acid
treatment
Confirm at least one colony per
sample according to MLG
Mix thoroughly approximately 2
minutes. Incubate at 41.5±1°C
Streak typical colonies to SBA
incubate 24±2 hr at 35±2°C
Raw ground beef
325g + 975 mL mTSB
Homogenize approximately
2 minutes. Incubate at
42±1°C for 15-24 hours
OMAMAN-35 B: Collaborative Study Protocol
ERP USE ONLY
January 2017
AOAC Research Institute
Expert Review Panel Use Only