Water Activity Testing
Water activity (aw) is a measurement of unbound or available water for microorganisms to use for growth.
Microorganisms will not grow below a certain water activity level. For example, most pathogenic bacteria will not grow below a water activity level of 0.90, 0.70 for molds, and 0.60 for all microorganisms. Other factors such as temperature, pH, and oxygen availability influence whether a microorganism will grow, but water activity is frequently the most important factor.
THC Analytical Lab analyzes water activity with a Novasina LabSwift water activity meter. Cured flower and pre-rolls are deemed to have passed water activity analysis if the water activity does not exceed 0.65 aw. Solid edible cannabis products are deemed to have passed water activity analysis if the water activity does not exceed 0.85 aw.