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C
rowley
et al
.:
J
ournal of
AOAC I
nternational
V
ol
.
97, N
o
. 2, 2014
451
Tables 2C–D, and Figures 2A–D, as supplemental data on the
J. AOAC Int.
website.
ALOA Chromogenic Agar
Confirmatory results obtained from the ALOA chromogenic
agar were identical to the results obtained from the OXA agar
specified by AOAC
993.12
. Out of a total of 447 positives
detected by the VIDAS LMX, 445 were confirmed positive using
OXA or ALOA selective agars.
Discussion
No negative feedback was reported to the study directors from
the collaborating laboratories in regards to the performance of
the VIDAS LMX assay or the ALOA chromogenic agar. Many
Table 4. Individual collaborator results for queso fresco
a
(125 g test portions)
VIDAS LMX
b
High–level test portions
Low-level test portions
Uninoculated test portions
Lab 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
1 + + + + + + + + + + + + – + + – – – – – + + – + – – – – – – – – – – – –
2
c
NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA
3 + + + + + + + + + + + + – + + – – – + + – – + + – – – – – – – – – – – –
4 + + + + + + + + + + + + – – – – + – + – + + – + – – – – – – – – – – – –
5 + + + + + + + + + + + + – – + + – – + – – – + + – – – – – – – – – – – –
6 + + + + + + + + + + + + – – + + + – + + – – – – – – – – – – – – – – – –
7 + + + + + + + + + + + + – + – – – + + + – + + + – – – – – – – – – – – –
8 + + + + + + + + + + + + – – + – – + – + + + + + – – – – – – – – – – – –
9 + + + + + + + + + + + + + + + + + – – – – – – – – – – – – – – – – – – –
10 + + + + + + + + + + + + – + + – + + – – + – – + – – – – – – – – – – – –
11
c
+ + + + + + + + + + + + + + + – – – – – – + – + – – – – – – – – – – – –
12 + + + + + + + + + + + + – + + + + – – + – + + + – – – – – – – – – – – –
13 + + + + + + + + + + + + – – – – – + + + + + – + – – – – – – – – – – – –
14 + + + + + + + + + + + + – – – + + – – + – + – + – – – – – – – – – – – –
AOAC
993.12
1 + + + + + + + + + + + + – – – – – + + + + + + + – – – – – – – – – – – –
2
c
NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA
3 + + + + + + + + + + + + + – – – – + – + – – + + – – – – – – – – – – – –
4 + + + + + + + + + + + + – + – – – + + + + – – + – – – – – – – – – – – –
5 + + + + + + + + + + + + – + + – + – + + – + – + – – – – – – – – – – – –
6 + + + + + + + + + + + + + + – – – + + + – – – – – – – – – – – – – – – –
7 + + + + + + + + + + + + + – – + – + + + – – – – – – – – – – – – – – – –
8 + + + + + + + + + + + + + – + + + + – – + + – – – – – – – – – – – – – –
9 + + + + + + + + + + + + + – – – – + – + – – + – – – – – – – – – – – – –
10 + + + + + + + + + + + + + + – – – + + + – + – – – – – – – – – – – – – –
11
c
+ + + + + + + + + + + + +
d
+ +
e
+ + +
f
+
f
– – +
f
+ + – – +
f
+
e
– – – – – +
g
+
g
+
g
12 + + + + + + + + + + + + + – – – + + – – – + – + – – – – – – – – – – – –
13 + + + + + + + + + + + + + + + + + + – – – – + – – – – – – – – – – – – –
14 + + + + + + + + + + + + – – + – + – – – – + + + – – – – – – – – – – – –
a
+ =
Listeria
spp. were detected in samples; – =
Listeria
spp. were not detected in sample.
b
Results were not used in statistical analysis; NA = not applicable (data not submitted).
c
Confirmed results from OXA and ALOA were identical for each test portion.
d
Result reported as
L. welshimeri.
e
Result reported as
L. innocua.
f
Result reported as
L. grayi.
g
Results reported as
L. ivanovii.
Candidates for 2016 Method of the Year
352