3M’s Petrifilm Salmonella Express System has been validated through AOAC International as a First Action Official Method of Analysis (OMA) for the detection of Salmonella in a variety of food products.
The system received OMA method number 2014.01 and can detect the pathogen in raw ground beef, cooked breaded chicken nuggets, raw ground chicken, raw ground pork, pasteurized liquid whole egg, fresh shrimp, fresh spinach, dry pet food and stainless steel.
It is a one test method in food and environmental samples and gives results in 44 hours.
3M Food Safety’s Molecular Detection Assay Salmonella was validated under the method last year.
Accurate and reliable
Tina Bauman, global marketing supervisor with 3M Food Safety, said the validation shows the system is considered to be accurate and reliable shown by the studies and review to achieve the method validations.
“AOAC methods are used globally to promote trade and to facilitate public health and public safety,” she told FoodQualityNews.com
AOAC has two programs to evaluate and approve methods through its Research Institute [RI], a subsidiary of AOAC International.
They are AOAC RI Performance Tested Method [PTM] and Official Method of Analysis [OMA].
Premier certification method
The PTM program has evolved into a premier method certification program for commercial and proprietary alternative methods, said Bauman.
“Methods certified as PTM were found to perform according to the manufacturer's documented claims and are used throughout the global market place. The PTM program offers certification as an endpoint for method evaluation or as an entry to method validation through the OMA program.
“The OMA program is internationally known for its rigorous scientific and systematic scrutiny of methods and, because of the level of scrutiny, a high level of confidence, credibility, and defensibility is ascribed to resulting OMAs.
“The OMA program provides for multi-laboratory validation and Expert Review Panel evaluation of a method.”
It gained certification from the AOAC Research Institute as a Performance Tested MethodSM, certification number 061301 prior to launch in 2013.
How it works
Bauman said the food sample is combined with the 3M Salmonella Enrichment Base plus 3M Salmonella Enrichment Supplement medium then incubated for 18 hours at 41.5 degrees Celsius.
“For high background flora, unprocessed foods, the sample is transferred into R-V R10 and incubated for 8-24 hours at 41.5 degrees Celsius. For low background flora, processed foods, this step is skipped and the food sample is transferred to the 3M Petrifilm Salmonella Express Plate.”
The tester then reviews the plate and circles up to five presumptive positive Salmonella colonies, she said.
“If presumptive positive Salmonella colonies are present, the tester can then add the 3M Petrifilm Salmonella Express Confirmation Disk to biochemically confirm all circled presumptive positive colonies at the same time.
“The plate and confirmation disk are incubated for four hours at 41.5 degrees Celsius.”
3M Food Safety said it would acquire validations as required by customers, whether accomplished within a country to meet local requirements or through global method validation schemes.
A review of the study for AOAC-OMA validation will be published by the Official Methods of Analysis of AOAC International and in the Journal of AOAC International.