Water Droplets on Cannabis Leaf

Water activity is generally known to be an essential factor when it comes to food safety in general. This principle applies equally to the cannabis industry. Monitoring water activity values during flower development with an emphasis on a measurement in the final stages of curing and before long term storage, plays a vital role in preventing the contamination of your cannabis crop. In addition, water activity is a significant predictor of mold and fungi growth or infection, particularly during the drying process.

Why Water Activity Levels Matter

During the drying process, water activity must be balanced. Cannabis buds dried to a water activity level above 0.65aw support mold growth, putting consumers at risk of inhaling mold spores or mycotoxins. This is particularly important when the product is in a state of storage or transport. On the other hand, if the buds are dried to a water activity level lower than 0.55aw, the risk of dry and fragile trichomes, breaking down and causing loss of potency, is very high. Thus, the recommended water activity range for cannabis storage is between 0.55-0.65aw. 

Accordingly, water activity is associated with the shelf life and other crucial factors affecting the quality of the final consumer product.

Water activity can be used to predict the likelihood of fungal contamination and the shelf-life of cannabis products, making it an effective tool for producers and retailers to ensure consumer safety. Growers can establish an ideal water level for each cannabis product by using these predictors and the information gathered.

Legalization and Regulations

With the legalization movement growing, government and federal bodies are eager to regulate the cannabis industry, both for recreational and medical products. Fungal or microbial contamination in dried buds, extracted oils, or even heavily processed products such as edibles pose significant health risks to consumers. 

Monitoring water activity allows producers to maintain safety standards and avoid unexpected contamination at all costs, guaranteeing a safe product, both for consumption and storage. Cannabis safety regulations are currently handled at a state level, and not all states require water activity testing. Still, common safety concerns indicate that producers and retailers concerned with consumer safety should regularly test and closely monitor water activity.

Mold Growth

Cannabis products with water activity levels above 0.70 aw but below 0.86aw may be considered shelf-stable but still support fungal growth. These products are not always classified as unsafe as most molds and yeasts don’t cause illness.

Although not considered unsafe, these conditions can lead to the production of mycotoxins and aflatoxins, which can cause consumers to experience health issues, especially when inhaled. Due to this, water activity should be maintained at below 0.70 aw, preferably below 0.65aw, or other precautions such as a preservative system or airtight packaging should be put in place.

The Importance of Water Activity

With so many factors essential to the quality of the cannabis or cannabis product reliant on maintaining ideal water activity, monitoring and maintaining water activity is a crucial part of creating a high-quality product. In states such as California, Nevada, Washington, and Oregon, water activity levels are part of federal regulations. But even when not federally required, continually testing monitoring water activity levels is crucial when creating a potent product and ensuring consumer safety.