Decarbing before introduction to solvent or in oil state

Do you decarb before or after you submerge the leaf in a solvent?

Almost everyone decarbs oil after extraction because it’s easier to know when it’s finished.


My experience is when you are dealing with an agricultural feedstock, things work out better when you do everything you can to pre-process the feedstock into a uniform state.
Drying and decarbing your size classified feedstock goes a long way towards making downstream processing predictable.

Decarbing large amounts of flower properly is a pain in the ass though when you can process first and decarb a much smaller amount of oil and be certain of when the process is complete. Decarbing flower always seemed like there was a certain amount of uncertainty involved without visual markers to identify where you are in the process.

if you want your terpenes at all, decarbing first is not generally considered a win.

when decarbing oil, the thermal transfer properties and end point are much better defined.

solvent of choice also makes a difference. the acidic cannabinoids may have different solubilities in your solvent of choice…wouldn’t want to deliberately lower your solubility right before extraction (super critical CO2 does better with decarbed material)


If activated carbon is part of your process I believe working with decarbed material is better.
It is rumored that THCA has a much greater affinity for AC than THC.
This fits my experience but I have never seen any real data on the subject.
Can you explain why decarbing before extraction loses terpenes, that does not fit my experience?

Terpenes are volatile & labile.
Decarb requires heat (or a catalyst).

Therefore: grabbing terps before heating gives mo’betta terpenes.

I too have heard rumors of affinity differences for acidic vs neutral cannabinoids. Waiting on in house analytics before I can verify.

Plenty of folks using AC on THCa etoh tincture who are not reporting significant losses, suggesting materials or technique may play a part in product loss.

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Myrcene boils at around 170 C at atmospheric pressure.
That is a reason to use inert gas blanketing instead of vacuum during decarb.
I prefer moderate vacuum and dry N2 purge as a compromise.
Cannot smell any terpenes in the exhaust of my rough pump or in the cold trap.