AOAC-RI ERP Book MICRO Sept 2016.pdf

OMAMAN-08/Collaborative Study Protocol March 2014 Expert Review Panel Use Only

3M Petrifilm SALX Collaborative Study

July 2013

OMA-2013-July-XXX

3M Appendix 8.5 – Flow Diagram for Raw Ground Beef (25g) 1 2 3 4 5 6 7 8 9 10 Homogenize 2 min 18-24h at 41.5±1°C

Ground beef

USDA

25g + 225ml BPW Stomach 2 min 22±2h h at 35±1°C

25g + 225mL 3M Salmonella Enrichment + Supplement (prewarmed to 41.5C)

3M SALX Method

0.1ml sample + 10ml mRV 0.5ml sample + 10ml TT (Hanja) 22-24h at 42 ± 0.5°C

0.1 ml + 10ml R-V R10 8-24h at 41.5±1°C

3M SALX Method Confirmation

Reference Method Confirmation

Hydrate SALX plate with 2.0 mL DI water, close top film gently, use 3M spreader to distribute diluent evenly, let sit on bench at least 1 hr prior to use, protected from light

0.5ml sample + 10ml TT (Hanja) 22-24h at 42 ± 0.5°C

Place room temperature SALX confirmation disk onto SALX plate, under top film and incubate 41.5±1°C for 4-5 h

0.1ml sample + 10ml mRV 22-24h at 42 ± 0.5°C

Streak to XLT4 (or DMLIA), BGS Incubate at 35±1°C Examine at 18-24h & 42-48h

Streak TT to XLTA (or DMLIA), BGS Incubate according to individual plate instructions.

Streak mRV to XLT4 (or DMLIA), BGS Incubate according to individual plate instructions.

Record confirmed + results: green to blue, blue to dark blue or black or have a blue precipitate around

Streak enriched sample onto gel of SALX plate. Close topfilm and incubate 41.5±1°C for 24±2 hr.

Transfer typical colonies to TSI/LIA slants 24±2h at 35±1°C AOAC Research Institute Expert Review Panel Use Only Transfer typical colonies to TSI/LIA slants 24±2h at 35±1°C

Transfer typical colonies to TSI/LIA slants 24±2h at 35±1°C

Circle presumptive Salmonella colonies (red to brown with yellow zone or gas bubble)

Biochemical/serological confirmations on all enrichments according to USDA/FSIS

Biochemical/serological confirmations on all enrichments according to USDA/FSIS

Biochemical/serological confirmations on all enrichments according to USDA/FSIS

Record sample as positive if typical colonies appear on SALX plate

DRAFT DOCUMENT

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