ERP Micro December 2019

bioMérieux GENE-UP® Listeria species 2 (LIS 2) AOAC ® Certification Number 121803

DISCUSSION OF MODIFICATION APPROVED JANUARY 2017 (7) The POD analysis between the GENE-UP Listeria species assay and the reference methods for all matrices indicated that there was no significant difference at the 5% level between the number of positive results by the two methods. The POD analysis between the GENE-UP Listeria species Assay presumptive and confirmed results for all matrices indicated that there was no significant difference at the 5% level. A summary of POD analyses is presented in Tables E and F. Liquid whole egg (100 g) For the low inoculation level of the GENE-UP Listeria species assay, there were 14 presumptive positives and 14 confirmed positives following the traditional and alternative method confirmation procedures. There were 18 confirmed positives for the reference method. For the high inoculation level, there were 5 presumptive positives and 5 confirmed positives following the traditional and alternative method confirmation procedures. There were 5 confirmed positives following the reference method. Whey powder (375 g) For the low inoculation level of the GENE-UP Listeria species assay, there were 19 presumptive positives and 19 confirmed positives following the traditional and alternative method confirmation procedures. There were 15 confirmed positives for the reference method. For the high inoculation level, there were 5 presumptive positives and 5 confirmed positives following the traditional and alternative method confirmation procedures. There were 5 confirmed positives following the reference method. Table E: GENE-UP ™ Listeria species Assay, Candidate vs. Reference – POD Results

Candidate

Reference

Matrix/Test Portion

Time Point

MPN a / Test Portion

Strain

N b

dPOD C f

95% CI g

x c

POD C d

95% CI

X

POD R e

95% CI

0.00, 0.43 0.48, 0.85 0.57, 1.00

0.00, 0.43 0.70, 0.97 0.57, 1.00

-0.43, 0.43 -0.43, 0.05 -0.43, 0.43

-

5

0

0.00

0

0.00

0.00

Liquid whole egg (100 g)

L. mono. BMX 12484

26 Hours

0.91 (0.70, 2.80)

20

14

0.70

18

0.90

-0.20

4.00 (2.19, >10)

5

5

1.00

5

1.00

0.00

Candidate

Reference

Matrix/Test Portion

Time Point

MPN a / Test Portion

Strain

N b

dPOD C f

95% CI g

x c

POD C d

95% CI

X

POD R e

95% CI

0.00, 0.43 0.76, 1.00 0.57, 1.00

0.00, 0.43 0.53, 0.89 0.57, 1.00

-0.43, 0.43 -0.03, 0.42 -0.43, 0.43

-

5

0

0.00

0

0.00

0.00

Whey powder (375 g)

L. innocua NCTC 11288

1.04 (0.53, 1.40)

26 Hours

20

19

0.95

15

0.75

0.20

>10 (2.34, >10)

5

5

1.00

5

1.00

0.00

a MPN = Most Probable Number is calculated using the LCF MPN calculator provided by AOAC RI, with 95% confidence interval b N = Number of test portions 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 confirmed candidate method result and reference method confirmed result POD values g 95% CI = If the confidence interval of a dPOD does not contain zero, then the difference is statistically significant at the 5% level