[angelgoob]

good thread. I think I'll go with 252 at 17 minutes lol.

[sadpanda]

i recently had to learn how to use the excellent tool Thin Layer Chromatography, its the only way my friend battling cancer has any way of knowing about the CBD levels in her plants.
Anyway amongst the various experiments i did a couple of decarboxylation runs also

[OranguTrump]

Originally Posted by olekingkole

Takes too long to warm up the oven to 290. Besides at 200 you don't have to be fussy about pulling it out at the exact right time. Be sure to have a good oven thermometer, cause ovens can be way off. Bottom line, 1 hour 45 minutes at 200.

This is the temp/time I used for my last batch of cookies - legendary at work now & being requested as purchases.

Spread out on a cookie tin & pretty much exactly the numbers you give. Worked 100%.

Plus - a looooong soak in the butter/oil. Low heat & lots of time & some stirring.

[SteelyX]

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






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





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:




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







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?
end

[SteelyX]

Had to post these in a second post

[SteelyX]

Wow sadpanda I'd love to learn more about TLC. Seems like the perfect budget quantitative test.

[PDX Dopesmoker]

Originally Posted by SteelyX

Wow sadpanda I'd love to learn more about TLC. Seems like the perfect budget quantitative test.

There is a pretty cool thread on the topic at the concentrates subforum

[SteelyX]

SadPanda- have you ever quantified the THC in those TLC runs?
Could you put all that in table form? Looks like it could be very helpful data.

[brown_thumb]

It seems logical (to me) that vacuum sealing in boilable bags would allow heat conversion of THC-A to THC while avoiding loss of THC and terpenes due to vaporization. Just simmer the bags at 210-212 degrees F then remove and allow to cool before opening. Leave sealed and freeze until needed.

[medman225]

Great thread. As for the boiling bags, id be worried about it getting. Too hot... at some point it will start to give off not vapor, but smoke(I am under the impression that you can in fact combust essential oils at a certain high temp, think of a super red hot dab)....
then. There is also the issue that if it gets hot enough to just vaporize and reform, there is pressure that is built up from this that I'd be worried about eventually popping the boiling bag... I did a test not too long ago in my vac oven, not under vacuum... I set it to 220, and put my oil in and simply closed the door... when I turned the pressure relief valve open not ten seconds later, a decent amount of pressurized air spewed out.

Something that I have not previously seen mentioned: since vacuuming/loss of atmosphere increases the given temp of the area... could you not do your decarbing at full vac at like 140 or so?
No one seems to be very concerned about losing terpenes, and as far as I know these strip away at lesser temps anyway... some of you might be asking why you would care, as thc is what your after, especially for those who use it for medical benefits... but what are we using it for? As a thc med that thc being given to the body is the main benefit, or the healing effects from ingesting cannabis extracts... for me it's the healing effects, which come from the high, and the high, imho, is not just constituted by thc. The terpenes present and the levels of said terps present, and even perhaps cbds to a lesser extent, all come into play when constituting a given strain/batch's High.... don't believe me? Have you ever smoked 99% pure thc crystals from guild extracts? It's nice, but isn't the holy grail by any means... the fact that they offer matching up said 99% pure thc to a known strains terp profile, pretty much backs up my claim.


Regarding this, and using cooler temps at longer times(remember it does it on its own at room temp) I am curious about the graphs. I'd like to see the results for lower temps, run longer. It seems to me those graphs only show one part, and if it kept going the others would keep climbing to roughly the same peak... maybe I'm wrong tho so someone tell me if I'm right or wrong.