Every year, millions of dollars’ worth of alcohol evaporates in a process coined the “angels’ share.”
The angels’ share refers to the portion of a spirit that evaporates from oak barrels during the aging process, be it water or alcohol. As temperatures and humidity fluctuate, the barrels breathe, allowing alcohol and water vapor to escape through the pores of the wood. In humid climates (Scotland), more alcohol evaporates, while in drier climates (Kentucky), more water evaporates (increasing the content’s potency).
This process influences the flavor and color of the resulting spirits, but approximately 5 gallons are lost in the first year from a 53-gallon barrel, followed by up to 2 gallons more per year thereafter. As much as half a barrel of whiskey can be lost to the angels’ share, depending on how long the spirit is aged.
Courtesy of Kenneth Morrow
The exact portion of terpenes lost to evaporation during the drying of cannabis varies greatly depending on methods utilized, with some studies showing a loss of more than 55% after a week of drying under improper conditions.
In one study by Samir A. Ross and Mahmoud A. ElSohly, approximately 31% of terpenes are lost after just one week of drying, and this percentage can increase to over 55% during a three-month drying and curing process. In one week, beta-myrcene, alpha-pinene, beta-pinene, and limonene percentages decreased significantly, with beta-myrcene decreasing by a whopping 55% when compared to an undried specimen.
Ross and ElSohly’s data showed that the fresh bud oil from their sample was comprised predominantly (92%) of lighter volatile monoterpenes such as myrcene, pinene, and limonene. Monoterpenes are more susceptible to evaporation (aka falling prey to the angels’ share) compared to heavier sesquiterpenes. This reaction is the reason why concentrates made from undried or fresh-frozen cannabis yield an elevated percentage of monoterpenes compared to an extract from dried plant material.
Even with proper drying and curing, 25% of available terpenes from the wet plant material typically evaporate. Fast drying and drying at elevated temperatures, such as in a hops kiln, will result in even more significant terpene loss. Some terpenes and other volatile organic compounds (VOC’s) evaporate at temperatures as low as 70°F (21°C).
Some have estimated that by the time cannabis reaches the point of sale, 60% to 90% of the original terpene content may be lost to evaporation from post-harvest processes.
Courtesy of Kenneth Morrow
How to Minimize the Angels’ Share
To minimize terpene evaporation, the first step is to utilize a dark, ventilated, and climate-controlled drying environment that maintains a temperature between 55°F and 70°F, and a humidity level between 55% and 60% over a 10-to-14-day period.
To further minimize terpene loss, it is advised to also control the temperature and humidity of all environments in which buds are exposed and at risk of evaporation, including curing environments, trimming spaces, and weighing and packaging rooms.
Even a pre-roll machine should be in a controlled environment to ensure a consistent product and minimal terpene evaporation. A good rule of thumb to follow is: If you smell cannabis, you are losing flavor.
A Method of Preserving Your Terpenes
Coutesy of Kenneth Morrow
I have a patented (in Canada, Mexico, and the EU, and pending in the U.S.) method of terpene isolation that yields a truly unique essence oil, the highest grade of an essential oil.
This method does not utilize heat, therefore avoiding thermal degradation associated with traditional terpene isolation methods such as steam distillation. It allows the grower to collect the terpenes traditionally lost to the drying process, or to fresh-freeze the plant material to stop the evaporation process before collecting the isolated terpenes as needed from the frozen wet plant material prior to drying.
Regardless of the condition of the biomass inputs, the method captures all monoterpenes and sesquiterpenes traditionally lost to the drying process. It does so organically and at the lowest cost of isolation without utilizing heat. The “essence oil” it yields is simply the closest isolate that truly reflects and represents the plant material it came from, be it cannabis, hops, lavender, rose, or any other plant or fruit that contains an aroma or oil.
The resulting terpene isolates are pharmaceutical grade and are a pure terpene composition without the presence of THC. The essence oil can be utilized in multiple ways, from vape products to pharmaceuticals, brewing, beverages, and any products regarding flavor and fragrance.
My isolation method and equipment system are capable of processing more than 2,000 kilograms per 24 hours, but can be as low as 20 pounds per day.
I’m currently seeking clients and investors in this terpene isolation technology for use in pharmaceuticals production, brewing, food flavoring, and fragrances, as well as in vape delivery devices. Licensing opportunities are in: the United States, Mexico, Canada, all of the EU, and most of the world.
