The Peel Plate® SA Microbial Tests are prepared culture methods used for the detection and enumeration of Staphylococcus aureus bacteria. Peel Plate SA test use a Baird Parker based medium for Staphylococcus detection.

These tests can be used for testing liquid foods, solid foods, and environmental sponge samples. The purple or blue colored colonies of the Peel Plate SA test are easily counted against the white background of the test plate. Each purple or green (blueish) colony with a white center represents a presumptive positive of 1 CFU of Staphylococcus aureus.

At 24 hours of incubation, check the plates for growth. If there is no growth, the test is complete. If growth is present, continue incubating for additional 24 hours (48 hours total). Any purple or green (bluish) colonies with a white center after 24 hour incubation are presumptive positive for Staphylococcus aureus. Mark all presumptive colonies at 24 hours and continue incubation.

At 48 hours, all purple colonies with or without a white center are presumptive positive for Staphylococcus aureus. Confirm that any green colonies with a white center at 24 hours are now purple. Count the total number of purple colonies on the plate and report as total presumptive positive for Staphylococcus aureus CFU/mL or CFU/g per dilution tested. Any red or green(bluish) colonies at 48 hours are negative and not counted as Staphylococcus aureus. If a colony is not purple (with or without a white center) at 48 hours it is not Staphylococcus aureus.

Benefits of the Peel Plate SA Test Include

• Ready-to-use. Just add sample/dilution. No spreading device needed.
• Etched grid lines for estimated counts.
• Colonies easily picked for additional isolation/classification.
• Convenient plate stacking for improved air circulation.
• Buffered formulation – pH not required for most samples.
• 12 month refrigerated shelf-life in a resealable foil zip bag.
• 47 mm diameter convenient for water filters and 100 mL water samples or larger.

FOR DETECTION AND ENUMERATION OF STAPHYLOCOCCUS AUREUS BACTERIA IN FOOD, SERIAL DILUTIONS OF FOOD, AND ENVIRONMENTAL SPONGE SAMPLES

The Peel Plate SA test is based on Baird Parker selective agar, and multiple colorimetric enzyme substrates to support growth and colorimetrically identify the growth of Staphylococcus aureus bacteria. The media also contains gelling and wicking agents which absorb and diffuse the sample. The method will provide a presumptive positive Staphylococcus aureus result that can then be confirmed following traditional confirmation procedures as outline in the FDA-BAM (Bacteriologic Analytical Manual).

The Peel Plate SA test is applicable to multiple food matrices incubated in the dark at 35-37 °C for 24 to 48 hours.

Samples should be 10-fold serially diluted into the FDA-BAM defined countable range of 20 to 200 CFU/mL.

Download Product Sheet

Peel Plate® SA Microbial Test Interpretation Guide