AOAC-RI ERP Book MICRO Sept 2016.pdf

Document 2 of 2 – 3M Petrifilm Salmonella Express PTM Study Report

Table 25. 3M Petrifilm SALX Method Comparison POD Results for Liquid Whole Egg (Internal Data) 1

3M Petrifilm SALX Method

Reference Method

x c

Strain MPN a /100g N b

95% CI g

e

d

dPOD CP f

95% CI

95% CI

x

Matrix Time Point

POD R

POD C

Pasteurized Liquid Whole Egg Vs. USDA/FSIS-

18 Hr Primary Enrichment –

0

5

0

0

0.00 - 0.43

0

0

0.00 - 0.43

0 -0.43 – 0.43

Salmonella

0.32 (0.14- 0.56)

20

6

0.3

0.15-0.52

4

0.2 0.08 – 0.42 0.1 -0.17 – 0.35

Enteritidis

0

5

0

0

0.00 - 0.43

0

0

0.00 - 0.43

0 -0.43 – 0.43

ATCC

13076 24 Hr Primary Enrichment – a MPN = Most Probable Number is based on the POD of reference method test portions across labs using the AOAC MPN calculator with 95% b N = Number of test potions c x = Number of positive test portions d POD C = Candidate method confirmed positive outcomes divided by the total number of trials e POD R = Reference method confirmed positive outcomes divided by the total number of trials f dPOD C = Difference between the candidate method confirmed results and candidate method confirmed result POD values 0.32 (0.14- 0.56) 20 6 0.3 0.15-0.52 4 g 95% CI = If the confidence interval of a dPOD does not contain zero, then the difference is statistically significant at the 5% level

0.2 0.08 – 0.42 0.1 -0.17 – 0.35

2 3 4 5 6 7 8 9

10 11 12 13 14 15 16