424-425 / 596
Table 1. Enrichment Protocols Using Demi-Fraser Broth Enrichment at 37 ± 1
°
C
1
2
Specific Instructions for Validated Methods
3
AOAC® Performance Tested Method
SM
#111501
4
5
6
7
In AOAC PTM studies, the 3M Molecular Detection Assay 2 –
Listeria
was found to be an effective method for the
8
detection of
Listeria
species
.
The matrices tested in the study are shown in Table 3. The limit of detection of the 3M
9
Molecular Detection Assay 2 –
Listeria
method is 1-5 colony forming units per validated test portion size (in Table 3).
10
11
12
Table 1. Enrichment protocols using Demi-Fraser Broth at 37 ± 1 °C
13
according to AOAC Performance Tested
SM
Certificate #111501
14
15
Sample Matrix
Sample Size
Enrichment
Broth Volume
(mL)
Enrichment
Time (hr)
Beef hot dogs, Queso
Fresco, Vanilla Ice
Cream, 4% Milk Fat
Cottage Cheese, 3%
chocolate whole milk,
romaine lettuce, bagged
raw spinach, cold
smoked salmon
25 g
225
24-30