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AOAC INTERNATIONAL
For ground beef enriched according to the reference method, 20 spiked and 5 unspiked samples
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were stomached for 2 minutes at 200 rpm with 225 mL buffered peptone water (BPW). Samples were
230
incubated.at35
°
C for 20 hours, then aliquots were removed for testing with the BAX® System method.
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For reference method testing, 0.5 mL BPW enrichment was added to 10 mL TT-Hajna broth and 0.1
232
mL BPW enrichment was added to 10 mL RVS broth according to the USDA-MLG method. In addition,
233
1 mL BPW enrichment was added to 9 mL TBG and 0.1 mL was added to 10 mL RVS broth according
234
to the HC Compendium method. All secondary enrichments were incubated at 42°C for 22-24 hours.
235
For ground beef enriched with the alternative BAX® System method, 20 spiked and 5 unspiked
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samples were stomached for 2 minutes at 200 rpm with 1.5 L of 46°C TSB + n. Samples were
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incubated at 39-42°C for 24 hours, with aliquots removed for testing with the BAX® System method
238
after 24 hours. For reference method confirmation from the alternative enrichment, 0.5 mL TSB + n
239
enrichment was added to 10 mL TT-Hajna broth and 0.1 mL BPW enrichment was added to 10 mL
240
RVS broth according to the USDA-MLG method. In addition, 1 mL BPW enrichment was added to 9
241
mL TBG and 0.1 mL was added to 10 mL RVS broth according to the HC Compendium method. All
242
secondary enrichments were incubated at 42°C for 22-24 hours.
243
For cream cheese enriched according to the reference method, 20 spiked and 5 unspiked samples
244
were blended with 225 mL lactose broth (LB) and allowed to sit at 25ºC for 55-65 minutes, then the pH
245
was adjusted to 6.8
±
0.2, if necessary. Samples were incubated at 35±2°C for 22-26 hours, then
246
aliquots were removed for testing with the BAX® System method. For reference method testing, 0.1
247
mL LB enrichment was added to 10 mL FDA RV broth (prepared from constituent components on the
248
day of testing) and incubated at 42°C for 22-26 hours. An additional 1 mL LB enrichment was added to
249
10 mL TT broth and incubated at 35±2°C for 22-26 hours.
250
For cream cheese enriched with the alternative BAX® System method, 20 spiked and 5 unspiked
251
samples were stomached for 2 minutes with pre-warmed (42°C) BAX® System MP media. Samples
252
were incubated at 39-42°C for 24 hours, with aliquots removed for testing with the BAX® System
253
method after 12 and 24 hours. For reference method confirmation from the alternative enrichment, 0.1
254
mL MP enrichment was added to 10 mL FDA RV broth (prepared from constituent components on the
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Dupont BAX Salmonella PTM Report
Modification Approved 2012 / PTM Certification No. 081201
For Expert Review Panel Use Only
Do Not Distribute