AOAC 2018 Methods

112  B ird et al . : J ournal of AOAC I nternational V ol . 102, N o . 1, 2019

Table 2018.01B. Comparative results for the detection of Cronobacter in 10 g powdered infant formula with probiotics test portions by the 3M MDA 2 – Cronobacter method versus ISO 22964:2017 in a collaborative study

CP a

CC b

C c

R d

C vs. R

dLPOD (C, R)

dLPOD (CP, CC)

N e X f POD

Inoculation level Statistic

Matrix

Lab

CP N X POD CC N X POD C N X POD R

Uninoculated control

Powdered infant formula 1 12 0 0.00 12 0 0.00 12 0 0.00 12 0 0.00 0.00 0.00 2 12 0 0.00 12 0 0.00 12 0 0.00 12 0 0.00 0.00 0.00 3 12 0 0.00 12 0 0.00 12 0 0.00 12 0 0.00 0.00 0.00 4 12 0 0.00 12 0 0.00 12 0 0.00 12 0 0.00 0.00 0.00 5 12 0 0.00 12 0 0.00 12 0 0.00 12 0 0.00 0.00 0.00 6 12 0 0.00 12 0 0.00 12 0 0.00 12 0 0.00 0.00 0.00 7 12 1 0.08 12 0 0.00 12 0 0.00 12 0 0.00 0.00 0.08 8 12 1 0.08 12 0 0.00 12 0 0.00 12 0 0.00 0.00 0.08 9 12 0 0.00 12 0 0.00 12 0 0.00 12 0 0.00 0.00 0.00 10 12 0 0.00 12 0 0.00 12 0 0.00 12 0 0.00 0.00 0.00 11 12 0 0.00 12 0 0.00 12 0 0.00 12 0 0.00 0.00 0.00 12 12 0 0.00 12 0 0.00 12 0 0.00 12 0 0.00 0.00 0.00 13 12 0 0.00 12 0 0.00 12 0 0.00 12 0 0.00 0.00 0.00 14 12 0 0.00 12 0 0.00 12 0 0.00 12 0 0.00 0.00 0.00 Estimate All 168 2 0.01 168 0 0.00 168 0 0.00 168 0 0.00 0.00 0.01 LCL g 0.01 0.00 0.00 0.00 –0.02 –0.01 UCL h 0.04 0.02 0.02 0.02 0.02 0.04 s r 0.11 0.00 0.00 0.00 LCL 0.10 0.00 0.00 0.00 UCL 0.15 0.15 0.15 0.15 s L 0.00 0.00 0.00 0.00 LCL 0.00 0.00 0.00 0.00 UCL 0.04 0.15 0.15 0.15 s R 0.11 0.00 0.00 0.00 UCL 0.10 0.00 0.00 0.00 LCL 0.12 0.21 0.21 0.21 P value 0.5158 1.0000 1.0000 1.0000 Powdered infant formula 1 12 6 0.50 12 6 0.50 12 6 0.50 12 6 0.50 0.00 0.00 2 12 7 0.58 12 7 0.58 12 7 0.58 12 7 0.58 0.00 0.00 3 12 5 0.42 12 6 0.50 12 5 0.42 12 6 0.00 –0.08 –0.08 4 12 5 0.42 12 5 0.42 12 5 0.42 12 5 0.42 0.00 0.00 5 12 4 0.33 12 4 0.33 12 4 0.33 12 4 0.33 0.00 0.00 6 12 5 0.42 12 5 0.42 12 5 0.42 12 5 0.42 0.00 0.00 7 12 8 0.66 12 6 0.50 12 6 0.50 12 6 0.50 0.00 0.16 8 12 6 0.50 12 6 0.50 12 6 0.50 12 6 0.50 0.00 0.00 9 12 6 0.50 12 6 0.50 12 6 0.50 12 6 0.50 0.00 0.00 10 12 5 0.42 12 5 0.42 12 5 0.42 12 5 0.42 0.00 0.00 MPN/ test portion (0.70, 0.57, 0.87) 11 12 8 0.66 12 8 0.66 12 8 0.66 12 8 0.66 0.00 0.00 12 12 7 0.58 12 7 0.58 12 6 0.50 12 7 0.58 –0.08 0.08 13 12 9 0.75 12 8 0.66 12 8 0.66 12 8 0.66 0.00 0.08 14 12 7 0.58 12 7 0.58 12 7 0.58 12 7 0.58 0.00 0.00

Low

Estimate

All 168 88 0.52 168 86 0.51 168 84 0.50 168 86 0.51 –0.01 0.01

LCL UCL

0.45 0.60 0.51 0.46 0.52

0.43 0.59 0.51 0.46 0.52

0.42 0.58 0.51 0.46 0.52

0.43 –0.12 –0.10 0.59 0.10 0.12

0.51 0.46 0.52

s r

LCL UCL