340 / 350
evaluate the mean of the log
10
values for statistical difference between two methods at the 95%
1
confidence level.
Repeatability of the Petrifilm RYM method and the reference methods was calculated
2
as the standard deviation (S
r
) for each contamination level for each matrix.
3
The performance of the Petrifilm RYM method in terms of enumeration and repeatability was equal to
4
or better than the ISO 21527:2008 parts 1 and 2 and the FDA BAM Chapter 18 reference methods at 48
5
and 60 hours, with the exception of high inoculation level of sour cream at 48 and 60 hours and the
6
medium and high levels of sandwiches at 48 and 60 hours.
7
8
Conclusion
9
These studies have demonstrated that the 3M Petrifilm Rapid Yeast and Mold Count Plate method is a,
10
specific, sensitive, and rugged method that detects and enumerates yeast and mold at 48 and 60 hours
11
from a variety of matrices, yielding equivalent values to the ISO 21527:2008 parts 1 and 2 and the FDA
12
BAM Chapter 18 reference methods.
13
References
14
1.
Bacteriological Analytical Manual, Chapter 18. Yeasts, Molds and Mycotoxins. April, 2001
15
revision.
16
17
2.
U.S. Food and Drug Administration. Code of Federal Regulations, Title 21, Part 58. Good
18
Laboratory Practice for Nonclinical Laboratory Studies.
19
20
21
22
3.
ISO/IEC 17025. General requirements for the competence of testing and calibration
23
laboratories.
24
25
44
AOAC Research Insti ute
Expert Review Panel Use Only
OMAMAN-16D/ PTM Report
ERP Use Only - December 2014