Microbiology Methods for ERP Review 3-2020

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results.

Results of Collaborative Study

The collaborative study involved a method comparison evaluation of the candidate method to the MLG 4.10 reference method for raw ground beef (80% lean). A total of 15 collaborators from 14 sites throughout the United States participated in this study. Each participant analyzed 36 unpaired test portions for the candidate method and the MLG reference method: 12 inoculated with a high level of Salmonella , 12 inoculated with a low level of Salmonella , and 12 non- inoculated controls. Of the 15 collaborators, 11 were included in the final statistical analysis. One laboratory was not able to complete testing and did not submit results. One laboratory did not perform the traditional confirmation procedure and were therefore excluded from the statistical analysis. Two laboratories (1 and 10) recovered the target analyte in their non- inoculated control samples and their data was not included in the statistical analysis. Tables 2020.1A and 1B summarize the results and POD statistical analysis of the collaborative study. Detailed results for each collaborator are presented in Table 2020.2A and 2020.2B. The individual collaborator test portion results are presented in Tables 1 and 2 of the Supplementary Materials. The concentration of Salmonella , and 95% confidence interval, in each inoculation level was determined on the day of initiation of analysis by the coordinating laboratory: 0.49 CFU/test portion (0.37, 0.63) for the low inoculum level and 3.43 CFU/test portion (2.72, 4.88) for the high inoculum level. The results of the APC analysis produced a range of 8.1 x 10 5 to 2.5 x 10 7 CFU/g for an average of 6.6 x 10 6 CFU/g. Complete APC results are presented in Table 3 of the Supplementary Materials. Temperature records obtained during the shipment of samples are presented in Table 4 of the Supplementary Materials.

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