Decarboxylation is a process that activates THC, the psychoactive compound in marijuana, through heat. The cannabis plant contains THCA, which must be converted into THC for users to feel high. When smoking or vaping weed, the heat causes decarboxylation instantly making THC immediately available for your body to absorb. Heat, time, and oxygen can contribute to decarboxylation, which is why it is important to keep your marijuana stored in an airtight container to preserve potency and freshness.
Decarboxylation is necessary when making edibles, since edibles are cool when consumed this process must occur prior to consumption. Cannabis flower is usually heated first in an oven to cause decarboxylation prior to infusing the weed into an oil or butter.