RI-ERP-FINALACTION-Recommendations

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

Collaborators will receive six to eight test portions to be separated into two separate test portions to be analyzed by the 3M Petrifilm RAC Plate method and reference method. Please review the reference methods carefully before initiating analysis. One temperature control sample will be included in the shipment to document the temperature of the sample upon receipt. Record all results on the data sheets provided.

3M Petrifilm RAC plates per dilution

Food Type

Reference Methods

Diluent

Raw easy peel shrimp Pasteurized skim milk Instant non-fat dried milk

2 at 32°C 2 at 35°C

FDA-BAM Ch. 3

BPD

SMEDP Ch. 6

BPD

2 at 32°C

SMEDP Ch. 6

BPD

2 at 32°C

1. Sample Preparation 1.1. Prepare a 1:10 dilution of each test portion 1.1.1. Skim milk and instant non-fat dried milk – 11mL/11g plus 99 mL of BPD 1.1.1.1. For skim milk, aseptically transfer 11 mL of skim milk to 99 mL BPD.Mix skim milk by shaking 25 times in 7 seconds through a one foot movement. 1.1.1.2. For instant non-fat dried milk, temper PBD to 40 ° to 45 °. Transfer 11g of instant non-fat dried milk to a sterile bottle or jar and add warmed diluent.Disperse sample completely before making any further dilutions 1.1.2. Raw easy peel shrimp - 50g plus 450 mL BPD (10 -1 ) and blend 2 minutes. 1.2. Prepare an additional 3 dilutions (10 -2 to 10 -4 ) using BPD. 1.2.1. 90 mL dilution blanks will be used to conduct the additional 3 dilutions for easy peel shrimp (10mL sample + 90mL BPD) 1.2.2. 99 mL dilution blanks will be used to conduct the additional 3 dilutions for pasteurized skim milk and instant non-fat dried milk (10mL sample + 90mL BPD) 2. 3M Petrifilm Rapid Aerobic Count Plate Method (please refer to the IFU for additional details) 2.1. Place two (four if plating shrimp) 3M Petrifilm RAC Plates on a flat, level surface for each dilution to be tested. 2.2. Lift the top film and with the pipette perpendicular dispense 1 mL of each dilution onto the center of bottom film of each plate. 2.3. Roll the top film down onto the sample. AOAC Research Institute

Expert Review Panel Use Only