330 / 350
No statistically significant difference was observed between all 3 levels analyzed between the two
1
methods. The p-values calculated at a 95% confidence level for the low, medium, and high levels were
2
0.7542, 0.9330, and 0.0613. The t-test indicated no significant differences between the 3M RYM method
3
and the ISO and FDA BAM methods. The 3M RYM method had a lower repeatability value than the ISO
4
and FDA BAM methods for the high level, with S
r
values, respectively, of 0.0276 and 0.0538. The ISO and
5
FDA BAM methods had a lower repeatability value than the 3M RYM for the low and medium levels with
6
S
r
values of 0.1390 and 0.1630 for the low level and 0.1104 and 0.1214 for the medium level. Detailed
7
results are presented in Table 28.
8
9
10
Table 28 .
Method Comparison Results for Frozen Ground Beef Patties at 60 Hours.
11
SD
SD
(S
r
)
(S
r
)
1
<10
<0
<10
2
<10
<0
<10
3
<10
<0
<10
4
<10
<0
<10
5
<10
<0
<10
1
4.0x10
1
1.6021
5.0 x10
1
2
3.0x10
1
1.4771
5.0x10
1
3
5.0x10
1
1.699
5.0 x10
1
4
6.0x10
1
1.7782
4.0 x10
1
5
8.0x10
1
1.9031
8.0x10
1
1
2.0 x10
2
2.301
2.2x10
2
2
2.2 x10
2
2.3424
2.3x10
2
3
2.0 x10
2
2.301
1.6 x10
2
4
2.0 x10
2
2.301
3.9 x10
2
5
3.8x10
2
2.5798
2.3x10
2
1 5.0 x 10
3
3.699
3.5441
2
4.4 x 10
3
3.6435
3.6335
3
5.2 x 10
3
3.716
3.6902
4
5.0 x 10
3
3.699
3.6532
5
4.8 x 10
3
3.6812
3.6232
3M RYM Petrifilm
ISO/FDA BAM
p-value
Ct/g
LOG MEAN
Ct/g
LOG
MEAN
Uninoculated
-
-
<0
-
Level
Sample
-
NA
<0
<0
<0
<0
Low
1.6919 0.163
1.699
1.7204 0.1104 0.7542
1.699
1.699
1.6021
1.9031
Medium
2.3451 0.1214
2.3424
2.3722 0.1309 0.933
2.3617
2.2041
2.5911
2.3617
High
3.6877 0.0276
3.5 x 10
4
3.6288 0.0538 0.0613
4.3 x 10
4
4.9 x 10
4
4.5x 10
4
5.2 x 10
4
12
13
Independent Laboratory Study
14
34
AOAC Research Institute
Expert Review Panel Use Only
OMAMAN-16D/ PTM Report
ERP Use Only - December 2014