ERP Micro December 2019

method (see Test Portion Analysis , above). A summary of the usage of the HT Amplification tubes PODs are presented in Table F and Table G , below.

Table F: Assurance® GDS for E . coli O157:H7 Tq, Candidate vs. Reference – POD Results: HT Amplification Tubes (Manual Sample Processing)

MPN a / Test Portion or CFU b /Cloth

Candidate

Reference

Test Portion Size

Matrix

N c

dPOD C g

95% CI h

a MPN = Most

x d POD C e

95% CI

X

POD R f

95% CI

5

0

0.00 0.65 1.00 0.00 0.40 1.00 0.00 0.50 0.60

0.00, 0.43 0 0.43, 0.82 16 0.57, 1.00 5 0.00, 0.43 0 0.22, 0.61 0 0.57, 1.00 2 0.00, 0.43 0 0.30, 0.70 2 0.23, 0.88 1

0.00 0.80 1.00 0.00 0.00 0.40 0.00 0.10 0.20

0.00, 0.43 0.58, 0.92 0.57, 1.00 0.00, 0.43 0.16, 0.61 0.18, 0.77 0.00, 0.43 0.03, 0.30 0.03, 0.64

0.00

-0.43, 0.43 -0.40, 0.12 -0.43, 0.43 -0.43, 0.43 0.16, 0.61 0.03, 0.88 -0.43, 0.43 0.12, 0.61 -0.16, 0.75

-

Beef trim i

375 g

20 13

-0.15 0.00 0.00 0.40 0.60 0.00 0.40 0.40

1.42 (0.90, 2.47)

5 5

5 0

2.93 (1.38, 6.27)

-

Frozen finely textured beef i

375 g

20 8

0.00 (0.00, 0.09)

5 5

5 0

0.46 (0.20, 1.02)

N/A j

Carcass cloth i

20 10

1 cloth

0.80

5

3

3.00

Probable Number is calculated using the LCF MPN calculator provided by AOAC RI, with 95% confidence interval b CFU/cloth = Results of the CFU/test area were determined by plating the inoculum for each matrix in triplicate c N = Number of test portions d x = Number of positive test portions e POD C = Candidate method confirmed positive outcomes divided by the total number of trials f POD R = Reference method confirmed positive outcomes divided by the total number of trials g dPOD C = Difference between the confirmed candidate method result and reference method confirmed result POD values h 95% CI = If the confidence interval of a dPOD does not contain zero, then the difference is statistically significant at the 5% level

i results for hand processing and PPMX sample processing procedures were same. j MPN not available for carcass cloth. Low and high inoculation levels CFU/cloth indicated. Table G: Assurance® GDS for E . coli O157:H7 Tq, Presumptive vs. Alternative and Traditional Confirmed – POD Result: HT Amplification Tubes (Manual Sample Processing)

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