Decarboxylation transforms inactive THCA into active THC. Choose your raw material and method: the tool instantly displays temperature, duration and expected efficacy.
Raw cannabis contains THCA (tetrahydrocannabinolic acid), a non-psychoactive molecule. Heat causes a chemical reaction that eliminates a carboxyl group (-COOH), releasing THC active. This is the decarboxylation, essential before any infusion or preparation of edibles.
Without decarboxylation, only 10 to 20 % of THCA spontaneously converts to THC when infused in hot fat. With correct decarboxylation in the oven, the following is achieved 75 %. The hermetically sealed bain-marie rises to 88 %.
The decarboxylation reaction follows temperature-dependent chemical kinetics. Below 95°C, conversion is too slow to be practical. Above 130°C, THC itself begins to degrade into CBN (cannabinol), a cannabinoid with sedative effects but no significant psychoactive potency. The optimal window is therefore 100-120 °C depending on the method.
| Method | Efficiency | Terpene preservation | Reproducibility | Material cost |
|---|---|---|---|---|
| Conventional furnace | 75 % | Average | Average | Null |
| Water bath jar | 88 % | Good | Good | Null |
| Sous-vide | 87–91 % | Excellent | Excellent | Medium (€80-150) |
| Dedicated machine | 89–92 % | Very good | Excellent | High (€150-300) |
The terpenes are the aromatic compounds in cannabis. They contribute to the'entourage effect, the synergy between cannabinoids and terpenes described by Russo (2011). Over-aggressive decarboxylation (high temperature, long duration) destroys these volatile compounds even before you infuse your cannabis.
The most volatile terpenes (α-Pinene, Myrcene) evaporate at 155-167°C. Staying below 120°C guarantees their preservation. This is why sous-vide, which operates at 95°C, is the benchmark method for top-of-the-range preparations.
The distillates and the RSO (Rick Simpson Oil) are already decarboxylated during manufacture, so there's no need to heat them again. The BHO (Butane Hash Oil) on the other hand, requires decarboxylation at low temperatures to avoid degrading its texture and residual terpenes.