Hygiena BAX System X5, User Manual

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Chapter III. The BAX® System X5 PCR Assays
BAX® System X5 User Guide 37
Using the Listeria monocytogenes Assay
Kit #KIT2023 (D15407201)
1. Enrich Samples
The
AOAC Research Institute
has validated the BAX® System for detecting
Listeria monocytogenes in a wide variety of foods, including raw meats, fresh
produce/vegetables, processed meats, seafood, dairy cultured/non-cultured, egg
and egg products and fruit juices and plastic surfaces.
This test kit’s performance was reviewed by AOAC Research Institute and was found to perform to the
manufacturer’s specifications.
Sample type Primary enrichment Secondary enrichment
Ground beef, ground
pork, ground
chicken, ground
turkey Demi-Fraser broth: Homogenize 25 g sample
with 225 mL pre-warmed (30°C) Demi-Fraser
broth. Incubate at 30°C for 22-26 hours.
UVM broth: Homogenize 25 g sample with 225
mL pre-warmed (30°C) UVM broth. Incubate at
30°C for 20-24 hours.
Transfer 100 µL enriched
sample to 9.9 mL pre-warmed
(35°C) MOPS-BLEB.
Incubate at 35°C for 18-24
hours.
Frankfurters and
pepperoni For 25 g - Homogenize 25 g sample with 225 mL
pre-warmed (30°C) Buffered Listeria Enrichment
Broth without antibiotics. Incubate at 30°C for 4
hours, then add antibiotics. Incubate at 30°C for
an additional 18-22 hours.
For 125 g - Homogenize 125 g samples with
1.125L of UVM media. Incubate at 30°C for 23-
26 hours
Transfer 100 µL enriched
sample to 9.9 mL pre-warmed
(35°C) MOPS-BLEB.
Incubate at 35°C for 18-24
hours.
Fish sticks, surimi,
langostinos, smoked
salmon Homogenize 25 g sample with 225 mL pre-
warmed (30°C) Buffered
Listeria Enrichment
Broth without antibiotics. Incubate at 30°C for 4
hours, then add antibiotics. Incubate at 30°C for
an additional 18-22 hours.
Transfer 100 µL enriched
sample to 9.9 mL pre-warmed
(35°C) MOPS-BLEB.
Incubate at 35°C for 18-24
hours.
Smoke Salmon Homogenize 25 g samples with 225 mL pre-
warmed Universal Pre-enrichment Broth.
Incubate at 35
o
C or 22-26 hours.
Transfer 100 µL enriched
sample to 9.9 mL pre-warmed
(35°C) MOPS-BLEB.
Incubate at 35°C for 18-24
hours.
Ice cream, milk (2%)
yogurt, soft cheese Homogenize 25 g sample with 225 mL pre-
warmed (30°C) Complete Selective Enrichment
Broth. Incubate at 30°C for 22-26 hours. Transfer 100 µL enriched
sample to 9.9 mL pre-warmed
(35°C) MOPS-BLEB.
Incubate at 35°C for 18-24
hours.
Cabbage slaw,
peas, spinach,
strawberries, apple
juice and orange
juice, queso fresco
cheese Homogenize 25 g sample with 225 mL pre-
warmed (30°C) Buffered
Listeria Enrichment
Broth without antibiotics. Incubate at 30°C for 4
hours, then add antibiotics. Incubate at 30°C for
an additional 18-22 hours.
Transfer 100 µL enriched
sample to 9.9 mL pre-warmed
(35°C) MOPS-BLEB.
Incubate at 35°C for 18-24
hours.
Environmental
sponges Sample a 4 x 4 in (10 x 10 cm) environmental
area with a sponge pre-moistened with D/E
Neutralizing Broth. Homogenize sponge with 190
mL pre-warmed (30°C) UVM. Incubate at 30°C
for 20-26 hours. Transfer 100 µL enriched
sample to 9.9 mL pre-warmed
MOPS-BLEB. Incubate at
35°C for 18-24 hours.