In layman’s term Decarboxylation is the process of activating cannabis usually to get the psychoactive effects. (We have a post describing decarboxylation in more details.) In order to decarboxylate cannabis we only need to heat it to certain degree and for certain amount of time.
As the baseline for my experiments I use the following chart:
The obvious solution to achieve this is to use oven but here is the problem: The household ovens are not accurate and the actual temperature can vary more than 20 degrees in relation to what has been set. I learned that after a few attempts when I decided to measure things more precisely and finally purchased a Infrared Thermometer (this one to be exact). In my case setting the oven to 120c (248f) seemed to be setting the average temperature, reaching as high as 140c (284f) and dropping to around 100c (212f). Unfortunately that does not have the same effect. Decarboxylate my weed for 30 minutes at 120c is not going to be equal to 15 minutes at 100 and 15 minutes at 140. Beside losing cannabinoids to vaporization, it also may result in THC degrading and converting to CBN and altering the effects into a more sedating quality. I’m sure there is a sweet spot to achieve good results with household ovens but it can only happen through trial and error and the results may not be reproduced using another oven.
Getting help from the same infrared thermometer to keep an eye on the temperature, I tried to decarboxylate my weed in cast-iron pan on the stovetop but stabilizing the temperature proved to be more difficult than expected. Perhaps a heavier cast-iron pan may have given me better results but again it would have been difficult requiring constant attention to the temperature at all times.
Using a double-boiler seemed to be the best solution considering it gives us a fairly accurate fixed temperature of around 100c (212f) but I couldn’t find a usable chart for the amount of time needed to decarboxylate weed at that temperature. In the past I used to make cannabutter using a double-boiler, boiling for 12-24 hours and it worked but I’m not sure if it gave the best results.
I could use this concept if only I could elevate the boiling point of water. Adding salt will elevate the boiling point by only 2-3c but we would need a way to make it reach close to 120c. It turns out adding pressure will have a more drastic effect than adding a solute. At pressure of 1 bar or 15 psi above the existing atmospheric pressure, water will boil at 121c (250f)! Jackpot! That or something close to that we can achieve with a household pressure cooker!
Standard pressure cookers are designed to cook food in 14.5-15 psi which translates to keeping the temperature between 120.6-121c (249-250f). We would also need a trivet/rack to put in the pressure cooker and separate our cannabis container from the bottom of the pressure cooker.
The process is simple. Put your buds in a container which can withstand high temperatures. I have tried mason jars along with a few other stainless steel containers. close the lid. Put the container securely on the trivet inside the pressure cooker. Fill the pressure cooker with enough water (depending on the pressure cooker it varies but the idea is just to have enough water not to run dry). Put it on the stovetop and wait until the steam starts hissing! That’s when you start the timer. If we want to go based on the chart we showed earlier, we will need to wait around 27 minutes but we would also have to account for the time it takes for the air inside the container to get hot. Depending on the container I would suggest setting the timer between 35-40 minutes.
When the time is reached, turn the heat off, wait for the pressure to drop and/or depressurize according to your pressure cooker manual and let the content cool down. Your buds are now activated. Enjoy!