4. AOACRIMicroMethods-2018Awards

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B ird et al .: J ournal of AOAC I nternational V ol . 98, N o . 3, 2015  773

3M Petrifilm RYM Count Plate high contamination level were identified as an outlier by the double Grubbs’ test for outliers. However, no evidence of physical cause or suspicion of cause was noted and it was determined that they would be included in the statistical analysis. There were no statistically significant differences at the 5% level in log transformed means between the 3M Petrifilm RYM Count Plate method and FDABAM/ISO 21257 methods, at any of the three contamination levels. 3M RYM Count Plate incubated at 25 ° C and enumerated at 60 h.— The mean log 10 counts of the 3MPetrifilmRYMCount Plate and FDA BAM/ISO 21527 results were compared statistically. One laboratory was identified in the FDA BAM/ISO 21527 high contamination level as an outlier by the Single Grubbs’ test and two laboratories in the 3M Petrifilm RYM Count Plate high contamination level were identified as an outlier by the double Grubbs’test for outliers. However, no evidence of physical cause or suspicion of cause was noted and it was determined that they would be included in the statistical analysis. There were no statistically significant differences determined between the 3M Petrifilm RYM Count Plate method and FDABAM/ISO 21527 methods at the 95% level or between the differences of means at all three contamination levels. 3M RYM Count Plate incubated at 28 ° C and enumerated at 48 h.— The mean log 10 counts of the 3M Petrifilm RYM Count Plate and FDA BAM/ISO 21527 results were compared statistically. One laboratory was identified in the FDABAM/ISO 21527 high contamination level as an outlier by the Single Grubbs’ test and two laboratories in the 3M Petrifilm RYM Count Plate high contamination level were identified as an outlier by the double Grubbs’ test for outliers. However, no evidence of physical cause or suspicion of cause was noted and it was determined that they would be included in the statistical analysis. There were no statistically significant differences at the 5% level in log transformed means between the 3M Petrifilm RYM Count Plate and FDA BAM/ISO 21257 methods, at any of the three contamination levels. 3M RYM Count Plate incubated at 28 ° C and enumerated at 60 h.— The mean log 10 counts of the 3M Petrifilm RYM Count Plate and FDA BAM/ISO 21527 results were compared statistically. One laboratory was identified in the FDABAM/ISO 21527 high contamination level as an outlier by the Single Grubbs’ test and two laboratories in the 3M Petrifilm RYM Count Plate high contamination level were identified as an outlier by the double Grubbs’ test for outliers. However, no evidence of physical cause or suspicion of cause was noted and it was determined that they would be included in the statistical analysis. There were no statistically significant differences at the 5% level in log transformed means between the 3M Petrifilm RYM Count Plate method and FDABAM/ISO 21257 methods, at any of the three contamination levels.

statistically. One laboratory in the FDA BAM/ISO 21527 low contamination level was identified as an outlier as defined by the Cochran’s tests for outliers. However, no evidence of physical cause or suspicion of cause was noted and it was determined that they would be included in the statistical analysis. There were no statistically significant differences at the 5% level in log transformed means between the 3M Petrifilm RYM Count Plate method and FDABAM/ISO 21257 methods, at any of the three contamination levels. 3M RYM Count Plate incubated at 25 ° C and enumerated at 60 h.— The mean log 10 counts of the 3M Petrifilm RYM Count Plate and FDA BAM/ISO 21527 results were compared statistically. One laboratory in the FDA BAM/ISO 21527 low contamination level was identified as an outlier as defined by the Cochran’s tests for outliers. However, no evidence of physical cause or suspicion of cause was noted and it was determined that they would be included in the statistical analysis. There were no statistically significant differences at the 5% level in log transformed means between the 3M Petrifilm RYM Count Plate method and FDABAM/ISO 21257 methods, at any of the three contamination levels. 3M RYM Count Plate incubated at 28 ° C and enumerated at 48 h.— The mean log 10 counts of the 3M Petrifilm RYM Count Plate and FDA BAM/ISO 21527 results were compared statistically. One laboratory in the FDA BAM/ISO 21527 low contamination level was identified as an outlier as defined by the Cochran’s tests for outliers. However, no evidence of physical cause or suspicion of cause was noted and it was determined that they would be included in the statistical analysis. There were no statistically significant differences at the 5% level in log transformed means between the 3M Petrifilm RYM Count Plate method and FDABAM/ISO 21257 methods, at any of the three contamination levels. 3M RYM Count Plate incubated at 28 ° C and enumerated at 60 h.— The mean log 10 counts of the 3M Petrifilm RYM Count Plate and FDA BAM/ISO 21527 results were compared statistically. One laboratory in the FDA BAM/ISO 21527 low contamination level was identified as an outlier as defined by the Cochran’s tests for outliers. However, no evidence of physical cause or suspicion of cause was noted and it was determined that they would be included in the statistical analysis. There were no statistically significant differences determined between the 3M Petrifilm RYM Count Plate and FDABAM/ISO 21527 methods at the 95% level or between the differences of means at all three contamination levels. Raw almond test portions were inoculated at a low, medium and high contamination level and were analyzed (Tables 6–9) for the enumeration of yeast and mold. Uninoculated controls were included in each analysis. Fifteen laboratories participated in the analysis of this matrix. 3M RYM Count Plate incubated at 25 ° C and enumerated at 48 h.— The mean log 10 counts of the 3M Petrifilm RYM Count Plate and FDA BAM/ISO 21527 results were compared statistically. One laboratory was identified in the 3M Petrifilm RYM Count Plate medium contamination results as an outlier by the Cochran’s test for outliers, one laboratory was identified in the FDA BAM/ISO 21527 high contamination level as an outlier by the Single Grubbs’ test, and two laboratories in the Raw Almonds

Discussion

No negative feedback was reported to the study directors from the collaborating laboratories in regards to the performance of the 3M Petrifilm RYM Count Plate. A few laboratories indicated difficulty in spreading the test portion liquid aliquot over the entire surface of the plate before the sample began to

03/10/2019