Decarboxylation is simply removing a carboxyl group (CO2+H) from the phytocannabinoid THCA to create the active THC, that will now fit the CB-1 receptor on certain cells. This process occurs simply through heating. You can use high heat for a short time, or medium heat for a longer time. High heat destroys much of the beneficial chemistry of the cannabinoids, terpinoids, and flavinoids.
The optimum temperature is 240ºF. for 30-45 minutes.
There is much opinion about the process, but this is a good place to start. As you may know, the Russians were doing this over 20 years ago.
Essential to the success of this process is the preparation of the plant material previous to heating. The plant material must be really dry. Run it through a blender to break up the material. Remove stems. Lay it out on a cookie sheet. Preheat oven to 240º, heat for 30-45 minutes. Follow with extracting the oil.
It is possible to perform the decarboxylation either on the extract, or with the dry plant material. Either way will work.
Why decarboxylation? If we are fighting cancer, we need to optimize the potency of treatment. THC kills cancer by shredding the mitochondria to disrupt its energy metabolism, while leaving normal cells untouched. THCA will not have this effect.
~ Dennis Hill