4. AOACRIMicroMethods-2018Awards

994 B ird et al .: J ournal of aoaC i nternational V ol . 99, n o . 4, 2016

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0.14) was obtained between presumptive and confirmed results, indicating no statistically significant difference between the presumptive and confirmed results. For the high inoculum level, 155 of 156 test portions (POD CP of 0.99) were reported as presumptive positive by the 3M MDA 2 – Salmonella method, with 155 test portions (POD CC of 0.99) confirming positive. For samples that produced presumptive positive results on the 3M MDA 2 – Salmonella method, 155 samples confirmed positive (POD C of 0.99). For test portions evaluated by the USDA/FSIS MLG reference method, 156 of 156 test portions produced positive results. A dLPOD C value of −0.01 (95% confidence interval, −0.04 to 0.02) was obtained between the candidate and reference method, indicating no statistical significant difference between the two methods. A dLPOD CP value of 0.00 (95% confidence interval, −0.03 to 0.03) was obtained between presumptive and confirmed results, indicating no statistically significant difference between the presumptive and confirmed results. For the uninoculated controls, 4 of 156 samples (POD CP of 0.03) produced a presumptive positive result by the 3M MDA 2 – Salmonella method, with three test portions (POD CC of 0.02) confirming positive. For samples that produced presumptive positive results on the 3M MDA 2 – Salmonella method, two samples confirmed positive (POD C of 0.01). For test portions evaluated by the USDA/FSIS MLG reference method, 2 of 156 test portions produced positive results. A dLPOD C value of 0.00 (95% confidence interval, −0.03 to 0.03) was obtained between the candidate and reference method, indicating no statistical significant difference between the two methods. A dLPOD CP value of 0.01 (95% confidence interval, −0.03 to 0.05) was obtained between presumptive and confirmed results, indicating no statistically significant difference between the presumptive and confirmed results. Detailed results of the POD statistical analysis are presented in Table 2016.01C and Figures 1 and 2.

Table 5. Results of Aerobic Plate Count for Collaborating Laboratories

Raw Ground Beef (CFU/g)

Creamy Peanut Butter (CFU/g)

Laboratory

5.8 x 10 5 4.4 x 10 6 4.0 x 10 1 8.3 x 10 6

2.2 x 10 2 3.4 x 10 2 3.4 x 10 2 1.0 x 10 2 1.9 x 10 2 1.2 x 10 2 1.9 x 10 2 3.2 x 10 2 3.1 x 10 2 4.1 x 10 2 2.2 x 10 1 3.1 x 10 2 1.0 x 10 1 NA NA

1 2 3 4 5 6 7 8 9

NA

3.3 x 10 7

NA

2.7 x 10 6 4.4 x 10 5

10 11 12 13 14 15 16

NA

1.7 x 10 6 4.5 x 10 5 6.6 x 10 3 1.3 x 10 6 1.2 x 10 5 2.3 x 10 5

NA

2 – Salmonella method, with 83 test portions (POD CC of 0.53) confirming positive. For samples that produced presumptive positive results on the 3M MDA 2 – Salmonella method, 82 samples confirmed positive (POD C of 0.53). For test portions evaluated by the USDA/FSIS MLG reference method, 77 of 156 test portions produced positive results. A dLPOD C value of 0.03 (95% confidence interval, −0.10 to 0.16) was obtained between the candidate and reference method, indicating no statistical significant difference between the two methods. A dLPOD CP value of 0.00 (95% confidence interval, −0.14 to

Figure 1. POD values of candidate method versus reference method for 325 g raw ground beef (73% lean).

03/10/2019