AOAC ERP MICRO AUGUST 2018

OMAMAN-44 A: Collaborative Study Manuscript Expert Review Panel Use Only August 2018

Pre-collaborative and Collaborative Report Peel Plate EB

Table 8. Peel Plate-EB High Volume (HV) Method (Singlet count) for Enterobacteriaceae at 24 hours vs ISO Methods 21528-1 & 2.

Fortified micro- organisms

Reference Method

r 2 h

Candidate Method

95% CI e

Mean diff. d

Matrix

Cont. level

ATCC No. (%injury)

Mean a

s r b

RSD r c

Mean

s r

RSD r

LCL f

UCL g

None

<0.1

na

na

<0.1

na

na

na

na

na

Infant Cereal with Probiotic j

Escherichia coli ATCC 25922 (Lyophilized)

Low

2.228 3.199 4.852 1.586 3.838 4.819 <0.1

0.125 0.088 0.110 0.354 0.023 0.108 na

6 3 2

2.216 3.203 4.889 1.551 3.559 4.592 <0.1

0.146 0.102 0.150 0.154 0.139 0.083 na

7 3 3

0.014 -0.004 -0.037 0.034 0.279 0.227 na

-0.049 -0.077 -0.114 -0.388 0.128 0.115 na

0.073 0.070 0.064 0.457 0.429 0.339 na

0.997

Medium

High None

na 10

na 22

Citrobacter freundii ATCC 8090 (Lyophilized)

Rice Infant cereal

low mid high

0.998

1 2

4 2

Table 8 continued. Peel Plate-EBHV Method (Duplicate count) for Enterobacteriaceae at 48 hours vs ISO Methods 21528-1 and 2.

Fortified micro- organisms

Reference Method

r 2 h

Candidate Method

95% CI e

Mean diff. d

Matrix

Cont. level

ATCC No. (%injury)

Mean a

s r b

RSD r c

Mean

s r

RSD r

LCL f

UCL g

None

<0.1

na

na

<0.1

na

na

na

na

na

Infant Cereal with Probiotic j

Escherichia coli ATCC 25922 (Lyophilized)

low mid high

2.245 3.205 4.877 1.561 3.830 4.855 <0.1

0.114 0.084 0.101 0.356 0.043 0.103 na

5 3 2

2.216 3.203 4.889 1.551 3.563 4.592 <0.1

0.146 0.102 0.150 0.154 0.133 0.083 na

7 3 3

0.029 0.002 -0.012 0.010 0.267 0.263 na

-0.030 -0.078 -0.131 -0.438 0.113 0.160 na

0.088 0.083 0.107 0.459 0.422 0.365 na

0.997

None

na 23

na 10

Citrobacter freundii ATCC 8090 (Lyophilized)

low mid high ERP Use Only 1 2 4 2

Rice Infant cereal

0.98

a Mean of 5 replicate portions, plated in duplicate, after logarithmic transformation: Log 10 [CFU/g + (0.1)f]. b Repeatability standard deviation.

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