1. Why is drying and curing so important in cannabis production?
Many natural products such as vegetables, fruits, and plants contain a substantial amount of water that must be removed to prevent mold and to maintain quality characteristics such as flavor, color, texture, and appearance, and cannabis flower is no exception. The moisture content of freshly harvested cannabis is approximately 75% and considered dried when the moisture level range is 5% to 13%. If the product is not dried correctly, entire batches can be lost due to mold and/or mildew contamination, making the drying step critical to a cultivation operation.
2. What are the ideal conditions for drying?
Placing the product in a sealed chamber with precise control over temperature, relative humidity, and air velocity is ideal for drying wet cannabis. Cultivators of high-end flower will set the temperature to about 60° F to 70° F and a relative humidity (RH)level of 45% to 55% to maintain CBD, THC, and terpenes. Given the importance of cleanliness and sanitation, the dryer should be designed with in-line filtration components and hygienic surfaces such as stainless steel.
3. What is the difference between drying for flower and drying for extraction?
Drying for flower requires a “low and slow” method, drying at a low temperature over several days or more; however, drying for extraction may be accomplished at a higher temperature in 24 hours or less. Many processors will raise the temperature inside the drying chamber to 85° F or more and increase airspeed to promote faster drying. A series of randomly placed pedestal fans does not promote the best air uniformity, so a system of engineered circulation fans and perforated baffles will be required to facilitate proper air distribution, especially in larger dryers.
4. What is the correct dryer size, and can you share examples?
The size of the dryer will depend on product quantity (measured in wet pounds or kilograms), whether the product is hung or placed on trays, and the processing method (flower or extraction). Typically, hung product will need more space when compared to racks and trays to load the equivalent amount of material (wet pounds). At Cann Drying Systems, we have provided small machines (200 wet pounds per batch) to niche growers and multiples of our largest machines (7,500-plus pounds per batch) to the biggest cultivation sites in the world.
5. What is the most energy-efficient and eco-friendly way to dry cannabis?
Selecting the most energy-efficient drying method is critical to the economics and long-term success of a cannabis facility. By managing a refrigeration circuit with state-of-the-art instrumentation and controls, heat pumps top the list as the preferred way to control temperature and RH in a sealed drying chamber efficiently. Heat pumps have a very low cost of ownership (low operating cost and minimal maintenance requirements), and also use electricity, which can be generated from renewable sources, thereby making this technology able to operate free of CO2 emissions.
Learn more: www.cannsystems.com
