Microbiology Methods for ERP Review 3-2020

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(AOAC Official Method 2011.17 ) or Bruker MALDI (AOAC Official Method 2017.09 )

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depending on availability.

5.5 In addition, all Solus One Salmonella enriched test portions will be confirmed using an alternative confirmation procedure. Each portion will be streaked directly from the primary enrichment onto selective agar, as described by BAM Ch. 5. Confirmation will

continue through to identification from the selective agar as described in 5.4.

6.0 8 9 Each level of each matrix will be analyzed and reported separately. Data may be excluded due to an 10 assignable cause, provided there is sufficient justification. Such data will not be included in the statistical 11 analysis. All data, even if excluded from the statistical analysis, will be reported (see Appendix J, Annex B 12 of the AOAC Guidelines for raw data table format). 15 16 The statistical analysis will be performed in accordance with the AOAC Guidelines (Appendix J ‐ , Annex F) 17 using the Least Cost Formulations, Ltd., AOAC Binary Data Interlaboratory Study Workbook (5). Reporting Raw Data 13 14 7.0 Statistical Analysis

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7.1

Estimate the repeatability standard deviation (s r ).

7.2 Estimate the reproducibility (s R ) by calculating the standard deviation of the laboratory

POD values (s POD ) and associated 95% confidence intervals.

7.3 Estimate the difference of cross ‐ laboratory POD (dLPOD) and associated 95% confidence

intervals. If the confidence interval of a dLPOD does not contain a zero, then the

difference is statistically significant.

7.3.1 dLPODc is the difference between the candidate and reference LPOD values. 7.3.2 dLPOD is the difference between the presumptive and confirmed LPOD values.

7.4

Graph POD R , LPOD C and dLPOD C by level with 95% confidence intervals.

7.5 Calculate false positive and false negative rates for the Solus One Salmonella method

using the presumptive vs. confirmed results.

8.0 32 33 Solus One Salmonella for Detection of Salmonella in Selected Foods and Environmental Surfaces 34 35 (Applicable to the detection of Salmonella in raw beef trim (375 g), instant non ‐ fat dry milk powder 36 (instant NFDM, 375 g), pasteurized liquid egg (100 g), raw salmon (25 g), cheddar cheese (25 g), 37 Romaine lettuce (25 g), whole black peppercorns, paprika powder and cinnamon powder (25 g sample 38 size), honey mustard onion seasoning and flavored ranch seasoning (375 g sample size), and stainless 39 steel and polystyrene surfaces) Solus One Salmonella – Method

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Safety Caution:

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