I think the best data we have so far of the Time & Temperature required for the efficient Decarboxylation of THC is from the GW Pharma patent application:

https://www.google.com/patents/EP1536810A2?cl=en

https://www.icmag.com/ic/picture.php...tureid=1701694




I graphed these and found best-fit curves in Excel. This is not rigorous, rather a rule of thumb sort of analysis.


The first 2 charts are
THC Decarboxylation vs Heating Time for various Temperatures,and
THC Decarboxylation vs Temperature for various Heating Times

https://www.icmag.com/ic/picture.php...tureid=1701685

https://www.icmag.com/ic/picture.php...tureid=1701686


Several conclusions can be drawn.

If you have good temperature control and want the most forgiving time window (for instance to allow time for sample to come up to temperature), you would choose 2.5 hours at 221° F.

If you have good time control but want the most forgiving temperature window (for instance with an imprecise oven thermostat), you would choose 260° F for 0.5 hours.

The best yield is found at 221° F for 2 hours. This may trend higher (speculating on extrapolation) if a slightly lower temperature is chosen. For example, 212° F for 2 hours may have good yield, as well as an being an easy temperature to control.

Good yields are also indicated for 260° F at 0.5 hours. Extrapolation indicates that excellent yields may also be seen at temperatures between 248-284° F for 0.25 hours.



These charts show some similarities to the widely circulated 1990 Journal of Chromatography chart:

https://www.icmag.com/ic/picture.php...tureid=1701684



And a couple of other views of the same data as above:

https://www.icmag.com/ic/picture.php...tureid=1701688





In light of all this, I have been getting excellent results by Decarboxylating and Infusing in one step. Oil, cannabis, and lecithin go into a boiling bag at 212° F for 2 hours, agitating frequently.

Does anybody else have hard data, or reproducible results to add?

Had to post image #6 separately

https://www.icmag.com/ic/picture.php...tureid=1701687

How often do you agitate during the cycle? I've been messing around with a few different methods. Lately I've been decarbing in a sealed glass mason jar inside my instant pot pressure cooker on high pressure mode which is 239 to 244 Fahrenheit for 40 minutes. I'm curious if you are getting a full decarb at that 210° temperature for only two hours. I would think that you would need to go 8+ hours at that temperature to get a full decarb but then again, I'm no scientist.

I have done batches in my magical butter machine at 220° for two and four hours and have never felt like it was as potent as lately when I've been heating the flower up to 240° before adding to the oil. I do feel like the flavor changes a little bit when heated that high tho and I'd like to maintain more of the fresh flower taste. I'm trying to figure out what the lowest temperature/time would be to get a proper decarb but also maintain that fresh flower taste.

i have tried various temp/time combinations and have found that a quick flash fry/constantly stirring @ 150C/300F till i smell a strong aroma, then remove from heat and place in a bowl to cool is working really well. it is so easy and quick to do, it takes around 2 minutes. ideally you don't want to see smoke or have your herb turn completely brown. i used a laser thermometer to gauge the temp my hot plate works at so i know what setting to use. if things get too hot remove from heat ASAP.

ozzieAI:

I decarb based on co2 bubbles and quite a bit hotter, more like U.... I concure... I cool immediately also....and fast then cool fast...

I only work with BHO tho...
usually 10 or 20g slabs..

decarb, then suck into syringes for measureed use later.