154-155 / 471
Table 2. Individual Collaborator Results for Full Fat Cottage Cheese (4%Milk Fat)
High-Level Test Portions
Low Level Test Portions
Un-inoculated Test Portions
1 2
3
4
5
6
7
8
9 10 11 12 1
2
3
4
5
6
7
8
9 10 11 12 1
2
3
4
5
6
7
8
9 10 11 12
3M MDA
Listeria
Lab
1
+
+
+
+
+
+
+
+
+
+
+
+
-
c
+
+
-
-
+
+
-
-
-
+
-
-
-
-
-
-
-
-
-
-
-
-
-
2
+
+
+
+
+
+
+
+
+
+
+
+
+
-
-
+
+
+
-
-
-
+
+
+
-
-
-
-
-
-
-
-
-
-
-
-
3
+
+
+
+
+
+
+
+
+
+
+
+
-
c
-
-
-
-
+
+
+
+
+
+
+
-
-
-
-
-
-
-
-
-
-
-
-
4
b
n/a
n/a
n/
a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
5
b
n/a
n/a
n/
a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
6
b
+
+
+
+
+
+
+
+
+
+
+
+
+
d
+
d
+
d
+
d
+
+
+
+
+
+
d
+
+
+
d
+
d
+
d
+
d
+
+
d
+
d
+
d
+
d
+
d
+
d
+
d
7
+
+
+
+
+
+
+
+
+
+
+
+
-
-
+
-
-
-
-
-
-
+
+
+
-
-
-
-
-
-
-
-
-
-
-
-
8
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
-
+
-
-
-
-
+
+
-
-
-
-
-
-
-
-
-
-
-
-
9
+
+
+
+
+
+
+
+
+
+
+
+
+
+
-
-
-
+
+
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
10
+
+
+
+
+
+
+
+
+
+
+
+
-
-
-
-
+
-
+
+
-
+
+
+
-
-
-
-
-
-
-
-
-
-
-
-
11
+
+
+
+
+
+
+
+
+
+
+
+
-
-
-
+
+
+
+
-
-
-
+
+
-
-
-
-
-
-
-
-
-
-
-
-
c
12
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
-
+
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
13
b
+
d
+
d
+
d
+
d
+
d
+
d
+
d
+
+
+
d
+
d
+
d
+
d
-
+
d
+
+
+
-
-
-
-
+
+
-
-
-
-
-
-
-
-
-
-
-
-
14
+
+
+
+
+
+
+
+
+
+
+
+
+
+
-
-
+
+
+
-
-
-
-
+
-
-
-
-
-
-
-
-
-
-
-
-
15
+
+
+
+
+
+
+
+
+
+
+
+
+
-
+
+
+
+
-
+
-
-
+
-
-
-
-
-
-
-
-
-
-
-
-
-
AOAC OMA 993.12
Lab
1
+
+
+
+
+
+
+
+
+
+
+
+
-
-
-
-
+
+
-
+
-
+
+
+
-
-
-
-
-
-
-
-
-
-
-
-
2
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
-
+
+
+
-
-
-
-
+
-
-
-
-
-
-
-
-
-
-
-
-
3
+
+
+
+
+
+
+
+
+
+
+
+
-
+
+
+
-
-
-
+
+
+
+
-
-
-
-
-
-
-
-
-
-
-
-
-
4
b
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
5
b
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
6
b
+
+
+
+
+
-
+
-
-
+
-
-
-
-
-
-
-
-
+
+
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
7
+
+
+
+
+
+
+
+
+
+
+
+
-
+
+
+
+
+
+
+
+
-
+
+
-
-
-
-
-
-
-
-
-
-
-
-
8
+
+
+
+
+
+
+
+
+
+
+
+
+
-
+
+
+
-
-
+
-
+
-
+
-
-
-
-
-
-
-
-
-
-
-
-
9
+
+
+
+
+
+
+
+
+
+
+
+
-
-
+
+
-
-
+
+
+
+
+
+
-
-
-
-
-
-
-
-
-
-
-
-
10
+
+
+
+
+
+
+
+
+
+
+
+
+
-
-
-
+
+
+
+
+
+
-
-
-
-
-
-
-
-
-
-
-
-
-
-
11
+
+
+
+
+
+
+
+
+
+
+
+
-
-
-
+
-
-
-
+
+
-
+
+
-
-
-
-
-
-
-
-
-
-
-
-
12
+
+
+
+
+
+
+
+
+
+
+
+
-
+
-
+
-
-
+
-
-
+
-
+
-
-
-
-
-
-
-
-
-
-
-
-
13
b
+
+
+
+
+
+
+
+
+
+
+
+
-
+
+
+
-
+
-
+
+
+
-
-
-
-
-
-
-
-
-
-
-
-
-
-
14
+
+
+
+
+
+
+
+
+
+
+
+
+
+
-
-
-
+
+
+
-
-
-
+
-
-
-
-
-
-
-
-
-
-
-
-
15
+
+
+
+
+
+
+
+
+
+
+
+
-
+
-
-
-
-
+
+
+
-
-
+
-
-
-
-
-
-
-
-
-
-
-
-
a
+=
Listeria
species were detected in samples; -=
Listeria
species were not detected in sample; n/a- lab did not participate in this matrix or results were not received
b
Results were not used in statistical analysis due to laboratory error;
c
Sample was presumptive positive on 3M MDA
Listeria
but confirmed negative indicating a false positive result;
d
Sample was presumptive negative on 3M MDA
Listeria
but confirmed positive indicating a false negative result
1
2
3
4
Candidates for 2016 Method of the Year
127