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VIDAS LMX & LPT Collaborative Study
April 19, 2013
OMA-2013-Apr-XXX
Appendix 9.5c – Flow Diagram for Soft Mexican Cheese, 125g LMX & LPT
1
2
AOAC
VIDAS
Matrix
125g + 375mL LPT broth
(prewarm to 18-25C)
Stomach then 24-30h at 30±1C
Confirm at least one
colony per sample
according to AOAC
(VITEK2GP or API
Listeria)
Streak to OX
Incubate 24-48 h
at 37C
Streak typical colonies
to TSAYE
24-48 h at 35C
Streak to ALOA
24-48 h at 35-37C
Confirm at least one
colony per sample
according to AOAC
(VITEK2GP or API
Listeria)
Streak typical colonies
to TSAYE
24-48 h at 35C
1ml
into
10 ml LPT broth
22-26h at 30±1C
0.25ml into
LMX
strip
and run VIDAS
NO heating
25g + 225ml selective
enrichment medium
(prewarm to 45C)
Blend 1-3 min
Incubate 48 h at 30C
Confirm at least one colony per
sample according to AOAC
993.12 (VITEK2GP or API
Listeria)
Adjust pH to 7.3, if necessary
At 48 h, streak to OX
Incubate 48 h at 37C
Streak typical colonies
to TSAYE
24-48 h at 37C
Option 1:
Transfer 0.5 ml into
LPT
strip,
heat 5±1 min on the Heat & Go, cool for
10 min, run VIDAS
Option 2:
Boil 1-2 mL 5±1 min at 95-100C,
cool for 10 min, 0.5 mL into
LPT
strip, run
VIDAS
3
DRAFT DOCUMENT
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