Is enumeration of TYM in marijuana infused product matrices possible with a 100,000 CFU/g action limit?

Yes. MGCs TYM in MIP enumeration process is still viable in certain jurisdictions such as Florida, due to the high action limit for TYM in MIPs of 100,000 CFU/g.

On April 10th, 2023, MGC released an update to their Total Yeast and Mold User guide.  One of the changes was an update to the process for detecting TYM in Marijuana Infused Product (MIP) matrices.  We now recommend an enrichment step prior to DNA purification to ensure the detection of low level contamination of TYM (1,000 CFU/g).  In jurisdictions with this threshold, the assay should be used as a screen.  If TYM is detected a plating method should be used to enumerate. 

This change was made due to difficulty detecting some yeasts at 1,000 CFU/g.  Initial internal validations for previous versions of our PathoSEEK TYM method were performed with Aspergillus, which is detectable down to 1,000 CFU/g.

Read more about our April 2023 update here.

Florida and the 100,000 CFU/g action limit for TYM

The state Florida allows a much higher contamination level of Total Yeast and Mold of 100,000 CFU/g for both flower and non - flower (MIP) matrices. It is possible that other jurisdictions will adopt similar thresholds in the future, but at the time of this publication only Florida has this regulation. A 1,000 CFU/g threshold for TYM is the more common threshold. Visit our microbial testing regulations reference page for more information on other jurisdictions.
At a threshold, or action limit, of 100,000 CFU/g, the PathoSEEK Total Yeast and Mold Count method is still acceptable for compliance testing. Our customers can continue using the TYM assay for enumeration without enrichment.
We have published a Florida version of our v2 PathoSEEK® Total Yeast and Mold Count with SenSATIVAx® DNA Purification and Grim Reefer® Free DNA Removal. Download here: