Decarboxylation of cannabis
The following information about decarboxylation was not written by Cannabis Chris, but was pulled from another site during part of my research for “Marijuana Decarboxylation: how to decarboxylate medical marijuana” and “What is Decarboxylation?“, as well as a future article with another method. This snippet about decarboxylation had too much good information for me to leave out.
After reading this information, along with a graph that shows decarboxylation temperatures, I will be doing some experimenting with a few more methods of decarboxylating marijuana and I will post the results here.
Anyway, here is some great information from one of the big pharma companies, about the decarboxylation process, some of the info is pretty boring, but please read it all. That way you will have the best understanding of the decarboxylation method you choose to go with…
“The decarboxylation step may be carried out prior to or after extraction with liquid CO2.
In a preferred embodiment the decarboxylation step … is conducted by heating the plant material to temperatures and for times which ensure at least 95% conversion of the acid cannabinoids from the acid form to their neutral form whilst ensuring thermal degradation of THC to CBN is less than 10%.
Decarboxylation of cannabinoid acids is a function of time and temperature, thus at higher temperatures a shorter period of time will be taken for complete decarboxylation of a given amount of cannabinoid acid. In selecting appropriate conditions for decarboxylation consideration must, however, be given to minimising thermal degradation of the desirable, pharmacological cannabinoids into undesirable degradation products, particularly thermal degradation of THC to cannabinol (CBN).
Preferably, decarboxylation is carried out in a multi-step heating process in which the plant material is:
i) heated to a first temperature for a first (relatively short) time period to evaporate off retained water and allow for uniform heating of the plant material; and
ii) the temperature is increased to a second temperature for a second time period (typically longer than the first time period) until at least 95% conversion of the acid cannabinoids to their neutral form has occurred.
Preferably the first step is conducted at a temperature in the range of 100° C. to 110° C. for 10–20 minutes. More preferably the first temperature is about 105° C. and the first time period is about 15 minutes.
If the plant material is derived from cannabis plants having a high CBD content (defined as >90% CBD as a percentage of total cannabinoid content), the second temperature is preferably in the range from 115° C. to 125° C., preferably about 120° C. and the second time period is in the range from 45 to 75 minutes, preferably about 60 minutes. More preferably the second temperature is in the range from 135° C. to 145° C., preferably 140° C. and the second time period is in the range from 15 to 45 minutes, preferably about 30 minutes. In another embodiment, most preferred for a mass of plant material greater than 4 kg, the second temperature is in the range from 140° C. to 150° C., preferably 145° C. and the second time period is in the range from 55–90 minutes. The latter conditions are preferred for processing amounts of, for example, 4–6 kg of starting plant material and the exact figures, particularly time, may vary slightly with increased mass.
If the plant material is derived from cannabis plants having a high THC content (defined as >90% THC as a percentage of total cannabinoid content), the second temperature is preferably in the range of 115° C. to 125° C., typically 120° C., and the second time period is preferably in the range of 45 minutes to 75 minutes, typically about 60 minutes. More preferably the second temperature is in the range of 100° C. to 110° C., typically 105° C., and the second time period is in the range of 60 to 120 minutes. In another embodiment, most preferred for a mass of plant material greater than 4 kg, the second temperature is in the range of 140° C. to 150° C., preferably 145° C., and the second time period is in the range of 45 to 55 minutes.
Most preferably the decarboxylation step is conducted at temperatures and for times which ensure at least 97% conversion of the acid cannabinoids to their neutral form, whilst ensuring thermal degradation of THC to CBN is less than 5%. …
The plant material used as the starting material for the extraction process is preferably ground, milled or otherwise processed to give a particle size of less than 2 mm, but preferably greater than 1 mm. Such treatment generally results in improved extraction of cannabinoids from the plant material, as packaging density is improved.”
I really like the detailed information on the decarboxylation process here. The 2-stage temperature method seems to be worth looking into.
If this information sparks any new methods of decarboxylation for you, then please comment with your method and results.