315 / 350
Table 12.
Method Comparison Results for Yogurt at 48 Hours.
1
SD
SD
(S
r
)
(S
r
)
1
<10
<0
<10
<0
2
<10
<0
<10
<0
3
<10
<0
<10
<0
4
<10
<0
<10
<0
5
<10
<0
<10
<0
1 2.8 x10
2
2.4472
2.6x10
2
2.415
2 2.0 x10
2
2.301
3.2 x10
2
2.5051
3
3.0x10
2
2.4771
3.0 x10
2
2.4771
4
3.2x10
2
2.5051
3.2 x10
2
2.5051
5
3.8x10
2
2.5798
3.4x10
2
2.5315
1 2.8 x10
3
3.4472
2.4x10
3
3.3802
2 2.4 x10
3
3.3802
3.6x10
3
3.5563
3 2.8 x10
3
3.4472
2.6 x10
3
3.415
4 2.6 x10
3
3.415
3.4 x10
3
3.5315
5 2.6 x10
3
3.415
2.4 x10
3
3.3802
1 2.0 x 10
4
4.301
2.2 x 10
4
4.3424
2 1.6 x 10
4
4.2041
1.6 x 10
4
4.2041
3 2.0 x 10
4
4.301
2.2 x 10
4
4.3424
4 1.6 x 10
4
4.2041
1.4 x 10
4
4.1461
5 1.3 x 10
4
4.1139
1.6 x 10
4
4.2041
p-value
Ct/g LOG MEAN
Ct/g LOG MEAN
Uninoculated
-
-
-
Level
Sample
3M RYM Petrifilm
ISO/ FDA BAM
-
NA
Low
2.462 0.1026
2.4868 0.0445 0.6343
Medium
3.4209 0.0279
3.4526 0.085 0.4633
High
4.2248 0.0787
4.2478 0.0895 0.6776
2
3
Yogurt 60 hours
4
No statistically significant difference was observed between all 3 levels analyzed between the two
5
methods. The p-values calculated at a 95% confidence level for the low, medium, and high levels were
6
0.3973, 0.4633, and 0.6776, respectively. The t-test indicated no significant differences between the 3M
7
RYM method and the ISO and FDA BAM methods. The 3M RYM method had a higher repeatability value
8
than the ISO and FDA BAM methods for the medium and high levels, with S
r
values, respectively, of
9
0.0279 and 0.0850 for the medium level and 0.0787 and 0.0895 for the high level. For the low level the
10
ISO and FDA BAM had higher repeatability value compared to the RYM method, with S
r
values,
11
respectively, of 0.0924 and 0.0445. Detailed results are presented in Table 13.
12
13
14
19
AOAC Research Institute
Expert Review Panel Use Only
OMAMAN-16D/ PTM Report
ERP Use Only - December 2014