AOAC ERP MICRO AUGUST 2018

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

method for Enterobacteriaceae, ISO 21528-1:2017 Microbiology of the food chain – Horizontal method 576

for detection and enumeration of Enterobacteriaceae – Part 1: Detection and Part 2: Enumeration. The 577

alternative method was not significantly different from the reference using either a singlet plate result 578

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or duplicate plate results at both the 24 and 48 h incubation periods.

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International collaborative study by 11 laboratories studying dried infant formula (dairy based)

containing probiotics demonstrated results not significantly different from the reference method with 581

mean log differences within -0.2 logs of ISO 21528-1 at the low concentration and within 0.2 logs of ISO 582

21528-2 at the medium and high concentrations. Repeatability and reproducibility values at both the 24 583

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and 48 h were comparable to the reference methods.

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The studies data support that Peel Plate EB method is equivalent to the ISO 21528- part 1 and part 2

reference methods within heat processed and dairy products, infant formula and cereals, stainless 586

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surfaces and chicken carcass rinses studied.

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Recommendations

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It is recommended that the Peel Plate EB be adopted as Official First Action status for the

enumeration of Enterobacteriaceae from pasteurized whole milk, butter, non-fat dry milk, vanilla ice 592

cream, powdered and liquid infant formula (milk based) containing probiotic, non-probiotic liquid infant 593

formula (soy-based), infant rice cereal (w/o probiotics), infant cereal with probiotics, chicken carcass 594 rinse with neutralized buffered peptone water, chicken carcass rinse with buffered peptone water and 595 ERP Use Only stainless-steel surfaces. 596 597

Acknowledgements

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