The first thing to bear in mind is that although the human body is comprised of around 60 per cent of water, THC itself, is NOT water soluble (i.e. it cannot be extracted, broken down or absorbed in water), therefore simply eating it is pointless as your body won’t be able to absorb the active ingredient.

You need to convert or extract your weed (THC) into something that your body can easily digest and metabolise, and for this we use either: fats, oils or alcohol*!

Ideally, you’ll also need to use something high in saturated fat, which will literally ‘soak up’ the THC (when properly extracted) and is then easily absorbed in the digestive system.

N.B. The percentage content of saturated is crucial to the potency of the finished product, not because THC won’t bind to other oils and fats etc, but because the human digestive system doesn’t process monounsaturated or polyunsaturated fats as effectively as saturated.

One of the best mediums to use is clarified butter (or Ghee as it is called in Asian cooking) as this contains no water molecules, and is almost 100 per cent saturated fat (regular butter still contains water and other impurities).
*If you prefer (or if your recipe calls for oil), you can substitute coconut oil ( around 92% saturated fat) or Palm Kernel Oil (around 86% saturated fat) instead.

The key to the extraction and binding process is prolonged, low heat (simmering) in order to thoroughly break down the cellular structure of the plant material you’re using, thereby freeing the TCH, but without losing any to vaporisation/evaporation. Once released, it can then ‘bind’ to the fat molecules of the butter or oil you’re using.
The length of time taken is also an important factor, but less so depending on the type of plant material you’re using. i.e. finely ground prime bud requires a shorter time to break down and release its THC content then say rough plant material like fan leaves and stems. These require extensive slow simmering in order to ‘dissolve’ the cellulose material binding in the THC at a cellular level.

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Cannabis Capsules A-step-by-step-guide.