Across the cannabis industry, flower quality at post-harvest cure barely resembles what consumers encounter at retail. Regulated cannabis markets produce some incredible bud. But inadequate post-harvest process control, misapplied product quality attributes and the tendency of terpenes to rapidly evaporate across the retail supply chain can leave customers wanting.
Cannabis quality and cannabis safety are not mutually exclusive. Cannabis, like many herbal medicinal products, is a highly variable organic material. Therapeutic compounds such as cannabinoids and terpenes must be carefully nurtured and properly protected in order to deliver the desired effect. First and foremost, however, producers must ensure that cannabis products are safe from contamination that could threaten public health, leading to unnecessary cannabis waste or a costly product recall and tarnished brand reputation.
Understanding Water Activity
Contemporary markets recognize the value of water activity, a widely accepted critical safety attribute, to facilitate both cannabis product freshness and reliability. Measured on a scale from 0 to 1, water activity indicates the amount of “free” water in a sample and therefore, the potential for microbial proliferation within a product or product package.
The United States Pharmacopeia and ASTM International recommend maintaining a consistent water activity range for post-harvest cannabis flower between 0.55 and 0.65, which correlates to 55-65% relative humidity. Controlling post-harvest practices to guarantee this range keeps dried cannabis flower safe from mold, yeast, bacteria and other harmful microorganisms qualifying water activity as part of an effective risk management plan.
Dry weed sucks
Across multiple jurisdictions, including California, a dryness epidemic runs rampant; no one is safe. Of the brands that consistently meet safety requirements by achieving an upper specification limit of 0.65 water activity, few achieve a water activity of 0.55 on the opposite end; many dip as low as 0.20. By that point, the vast majority of a flower’s precious terpenes have evaporated, resulting in a harsh, dry smoke bereft of flavor and medicinal value.
Producers who must abide by strict cannabis compliance standards often fail to synthesize critical safety attributes, such as water activity, with desirable consumer product quality specifications. Over-dry retail cannabis, which falls below 0.55 water activity is the result, with consumer disappointment, poor brand impression and retail defeat not far behind.
Achieving Product Parity
But safety is only one part of the consumer-quality paradigm. Exceptional, consumer-focused quality is earned at the production level where brands recognize that a positive consumption event is defined by sensory markers — flavor, color, burn rate, material consistency, etc. — that are directly related to the flower’s storage conditions. Water activity is the critical control that supports this sensory adventure, making it less a circumstantial byproduct and more an intentional brand standard.
Effect is also qualified by the psychotropic promise of cannabis flower. Unfortunately, inflated potency claims and inaccurate labeling, due to laboratory malfeasance, also impact consumers. Compliance samples may be dried to unfathomably low water activity levels to increase the percent by weight of THC during compliance testing; standardizing a water activity range for compliance tests may contribute to more accurate cannabis product potency claims and, therefore, a more reliable consumer experience.
In this case, the best offense is a good defense. To succeed in a consumer marketplace and mitigate operational risk, quality must be recontextualized as the sum of its parts — safety and consistency. Quality is the key to a robust risk management plan.
By identifying appropriate quality markers, such as water activity, then applying post-harvest process control to ensure quality attributes are consistently produced, operators can harmonize public health directives with consumer desire, to win long-term commercial success.
Claire Erickson serves as industry programs manager at Boveda Inc., the global leader in two-way humidity control. She focuses on strategic integration, the production of safe, high-quality cannabis, competitive landscapes, open conversation and global systems development.