I used 1/2 ounce of weed, decarbed it in my Ardent Nova, then I infused it in 1/2 cup of MCT coconut oil. After straining and pressing the oil out of the weed it gave me roughly 2.5 fluid oz (less than 1/3 of a cup). How do I calculate the loss of oil for potency? Nobody ever talks about this.
You will always lose some oil or butter or whatever you are infusing after draining and straining. Likewise, I always start with at least 1/4 cup or so more than what I hope to get back. For instance, if I want a cup of infused butter, I will start my infusion with 1 1/4 cups.
I do notice some cannabis strains seem to absorb more than others, so it is hard to be consistent and know exactly what each batch will be, but starting out with an extra 14 cup of oil will account for most, if not all, of it.
Also, you will notice the volume loss in cannabis infusions a lot more when you are only infusing small amounts like the 1/2 cup you mentioned above.
It also sounds to me, in this particular case, 1/2 cup of oil would barely be enough oil to cover 1/2 ounce of cannabis, so first off I would advise using more oil for the infusion, then add a little extra to also account for absorption. When infusion you need enough medium to totally soak the cannabis plus some extra.
When it comes time to calculate the dosing, calculate on what you have left after draining and straining. In other words when it asks amount to be infused in the dosing calculator, enter what you ended up with after straining).
Cheri's Dosage Calculators
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