RI-ERP-FINALACTION-Recommendations

OMA 2015.13: Collaborative Study Protocol Expert Review Panel Use Only September, 2017

1.

INTRODUCTION The goal of this collaborative study is to estimate the following performance parameters of the 3M™Petrifilm™Rapid Aerobic Count (RAC) Plate Method:repeatability (s r ) and reproducibility (s R ), standard deviations,mean difference and reverse transformed difference of means with 95% confidence intervals. Test portions from 4 different contamination levels will be sent to collaborators where they will perform the 3M Petrifilm RAC Plate and the FDA BAM Chapter 3or the Standard Methods for the Examination of Dairy Products reference method. The following foods will be tested: instant non-fat dried milk (11g), pasteurized skim milk (11mL) and raw easy peelshrimp(50g). 1.1. Description of the 3M™Petrifilm™Rapid Aerobic Count Plate The 3M™ Petrifilm™ Rapid Aerobic Count (RAC) Plate is a sample-ready culture medium system. 3MPetrifilm RAC Plates contain nutrients, a coldwater- soluble gelling agent, and a dual-sensing indicator technology that facilitates colony enumeration in 24 hours for most food matrices. 3M Petrifilm RAC Plates are used for the enumeration of aerobic bacteria in the food and beverage industries. 1.2. Summary of 3M Petrifilm RAC Count Plate PTM/Precollaborative Study The results of the PTM study demonstrated the 3M Petrifilm RAC Plate method to be equivalent to or better than the average log counts obtained by FDA BAM Chapter 3or Standard Methods for the Examination of Dairy Products (SMEDP) reference methods for the sixteen matrices evaluated: raw ground beef, raw ground pork, raw ground turkey, chicken carcass rinsate, fresh swai, fresh tuna, fresh tiger shrimp, easy-peel shrimp, cherry tomato wash, frozen blueberries, Mediterranean apricots, creamy salad dressing, fresh pasta, vanilla ice cream, instant non-fat dried milk, and pasteurized skim milk. The 3M PetrifilmRAC Plate method had higher repeatability in 26 out of 51 contamination levels evaluated. The results of this evaluation indicate that the 3M Petrifilm Rapid Aerobic Count Plate method is a rapid and accurate alternative to the reference methods for enumeration of aerobic bacteria in the food products tested. In the independent laboratory validation study, there was a significant difference in repeatability between the 3M Petrifilm RACPlate method and the reference methods for 3 of the 15 contaminations evaulated. For raw easy peelshrimpthe 3M Petrifilm RACPlate method enumerated more organisms than the FDA BAM method (p<0.05) at the medium and high microbial load contamination levels. The FDA BAM method enumerated more organisms that the3M Petrifilm RAC Plate method for the low microbial load contamination level. There were statistically significant differences in the ruggedness testing associated with temperature and diluent. However, with four exceptions, the

AOAC Research Ins itute Expert Review Panel Use Only