548 / 596
in the candidate presumptive and confirmatory results, dPOD
CP
;the presumptive candidate results
1
that confirmed positive, POD
C
(= POD
CC
);the reference method, POD
R
, and the difference in the
2
confirmed candidate and reference methods, dPOD
C
. POD analyses were conducted for the
3
MDA2 -
Listeriamonocytogenes
test points and compared to the appropriate reference method
4
results. The pre-validation target analyte background screen results and APC results are
5
presented in Table 5. The heat stress data for selected matrices are presented in Table 6. The
6
inoculum levels for each environmental surface are presented in Table 7. A summary of POD
7
analyses [13] are presented in Tables 8-15. As per criteria outlined in Appendix J of the Official
8
Methods of Analysis Manual [13], fractional positive results were obtained for all matrices.
9
10
Internal Study
11
12
Raw Chicken Leg Pieces (25 g) – 28 hour Primary Enrichment
13
14
For the low inoculation level of the MDA2 -
Listeria monocytogenes
assay, there were 10
15
presumptive positives and 10 confirmed positives following the USDA/FSIS MLG 8.09
16
reference method confirmation procedure. There were 12 observed positives for the reference
17
method. For the high inoculation level, there were 5 presumptive positives and 5 confirmed
18
positives following the USDA/FSIS MLG 8.09 reference method confirmation procedure. There
19
were 5 confirmed positive following the reference method.Detailed results of the POD analyses
20
are presented in Tables 8 and 12.
21
22
Bagged raw spinach
23
24
For the low inoculation level of the MDA2 -
Listeria monocytogenes
assay, there were 9
25
presumptive positives and 10 confirmed positives following the ISO 11290-1/A1 reference
26
method confirmation procedure resulting in 1 false negative. There were 10 observed positives
27
for the reference method. For the high inoculation level, there were 5 presumptive positives and
28
5 confirmed positives following the ISO 11290-1/A1 reference method confirmation procedure.
29
There were 4 confirmed positives following the reference method.Detailed results of the POD
30
analyses are presented in Tables 8 and 12.
31
32
33
Cold smoked salmon
34
35
Compared to FDA-BAM
36
For the low inoculation level of the MDA2 -
Listeria monocytogenes
assay, there were 10
37
presumptive positives and 10 confirmed positives following the FDA/BAM Chapter 10 reference
38
method confirmation procedure. There were 7 observed positives for the reference method. For
39
the high inoculation level, there were 3 presumptive positives and 3 confirmed positives
40
following the FDA/BAM Chapter 10 reference method confirmation procedure. There were 5
41
confirmed positives following the reference method.Detailed results of the POD analyses are
42
presented in Tables 8 and 12.
43
44
Compared to ISO 11290-1/A1
45