We’re going to talk about burning some carbs.
Whether you are a medical marijuana patient, recreational user, or casual connoisseur, it pays to ‘decarb’ your herbs before consuming them. Just like he name suggests the process of decarbing cannabis is exactly that. Applying heat allows the THCA in the cannabis to lose a single carbon atom to become the more biologically stimulating THC. As borrowed from Wikipedia, “upon heating, Δ9-Tetrahydrocannabinolic acid decarboxylates to give the psychoactive compound Δ9-Tetrahydrocannabinol.” This process is called decarboxylation or decarbing.
We’ve all done a similar thing every time we light up. When you smoke or vape marijuana, the plant material is decarbed by the flame or by the vaporizer. However, if you are planning to cook with cannabis and you are seeking the full psychoactive effect it is vital that you decarb your cannabis before you go all Jamie Oliver in the kitchen.
Raw cannabis contains a lot of THCA, which is not really psychoactive in its raw state. When you smoke cannabis, the THCA molecule loses its carboxylic group (COOH) in the form of water vapor and carbon dioxide and becomes THC. Through applying heat, THCA becomes THC and the marijuana becomes increasingly psychoactive.
Image via montanabiotech.com
There are a number of ways to decarb your dried cannabis. The variable factors are naturally heat and time. The conventional method of decarbing involves simply placing the herb on a (ungreased) baking sheet with enough space for the air move in and around every bud. It helps to break it up with your hands first. Preheat your oven to 240°F and bake-the-shake for 20 to 40 minutes.
Check on it periodically (i.e. 10 min. intervals) just to make sure it’s not burning up. What you’re looking for is that the buds are toasting evenly. After about 40 min. you should have golden brown buds.
The advice offered by Cannabis Culture is: “When the marijuana is crispy and brittle you can be assured that the carboxyl group has been removed from the cannabinoids and they are ready for extraction.” Decarbing is a handy trick to get the most out of your marijuana, but there are trade-offs. It has been suggested by medical marijuana patients that decarbing can really help with edibles but may be less effective when the extracts are to be used in topical pain relievers.
If you are planning on producing tinctures or creams it may be better to use an ice or alcohol concentrate extraction method. (You can read more about that process here).
Some vaporizers bake the plant matter at relatively low temperatures and it is certainly possible to use the ‘ash’ from a true vaporizer (e.g. Arizer, Atmos, Volcano, etc.) for making edibles because the cannabis is already decarbed. The only caveat I would add to this is that it can taste like bitter disappointment when used in cannabutter recipes. In particularly bad cases it may cause involuntary retching as your look for the Sriracha to kill the after-taste in your mouth.
Cannabis can be decarbed in a microwave as well.
The moisture created in a microwave is a better conductor of heat and as such is far more efficient at decarbing your marijuana than the dry air of a convection oven. Nuke the buds for 2-3 minutes. They won’t get much hotter than boiling water (100°C, 212°F).
Temperature matters. The Cannabis.com forums provided a great resource for the various temperatures by which the active compounds (Phytocannabinoids) in cannabis are activated. If you’re using an oven, be sure to invest in a good thermometer to ensure that the temperature is exactly where you want it to be to get the results you’re looking for. Laser thermometers are pretty cool and easy to use.