Decarbing gone wild

im wondering why m losing thc potency. we decarb at a ten to 1 ratio e
200 proof ethanol extraction threw a rotovape btw.about 2000 grams at a time usually,went from 90 percent to 75 percent without hanging any method so i guess my question is what would be the most common factor.qaulity of trim? to much carbon or is the testing facilities full of shit

tested after short path btw

  1. probably not a decarb issue issue. I would recommend starting here
  1. I don’t understand “losing potency”. That implies starting with 90% and ending with 75%, which I don’t believe is what you’re trying to convey. At a guess you’re saying that “I’ve run almost the same method multiple times, and I’ve tested at 90% THC in the past, but recently the output has been testing lower”. if your etoh crude is well made, you should be in the 65% THC range going into SPD. 65%=>75% is gaining potency, even if it’s not the gain you’re used to.

The standard answer is “show us a picture” ie: what does the chromatogram look like? Isomerization or degradation is the first place to look. low vacuum is often the primary cause. although acid activated carbon in the boiling flask has also taken some blame.

  1. how does one decarb in 10:1 ethanol? with a BP of ~78C I would expect the solvent to leave before much decarb happend. I find that recovering 15gal of tincture at 78C over 12hrs does lead to complete decarb…but recovering 5 gal in 4hrs does not.
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sorry i was thinking faster than i type, 4 months ago our lab results were in the 90s, havent changed any methods however now the results are much lower, around the 70s

are you checking your temperature when you are running this? are you mixing strongly?

Yeah, that was my assumption too. Used less solvent this roto run. It def brought down the decarb time. Next issue to fix is the spinbar. Getting burnt material in the bf even tho i start direct after decarb at 125c. Got bf to 135 and poured in the crude. Thought i had the spinbar going, but after the run there is a lot of hardened material in the bottom. Might just be the last stuff that gets cooled down when fluid hits it.

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yes it is decarbing at 220

switched to decarbing on a steel pot and hot plate old method was decarbing in the roto but starting noticing difference before i switched

heating mantle with mag stir, 120C, minimum 4 hours

I replied to your query in a new thread. because your question has zero to do with decarb. something you yourself appear to believe, because you told us “no changes” and then modified that to “changed my decarb, but this happened later”.

I understand it might take a bit for you to get chromatograms, but you really ought to visit said thread if you want to solve your potency issues.

them be sugars. you wants them gone anyway.

this is why you need in house analytics when you can test the “WTF is this” and confirm it’s not your target cannabinoid, you can figure out what’s going on waaay faster.

see if you can turn them to taffy and pull them in the rotoflask. Id try dropping to 60C or maybe even 30C without rotation when you’re almost done. to see if you can get them to separate out and maybe stick. pull them (hook?) . then take the temp back up to finish decarb. I don’t know if the MCT is a requirement. I don’t think so. the longer you cook them, the easier they semm to be to separate.

you can also let them caramelize then char. 'cept the burnt taste lingers (I’ve not tried distilling the burnt taste out, that should work). you want to ditch as much ballast as possible before hitting the boiling flask. to avoid as many side reactions as possible.

yeah you went from 2.5l to 1.75l & it took forever, because you still had more than 20% ethanol in there when you started counting. :stuck_out_tongue_winking_eye:

edit: the MCT might be important. at least for lowering the viscosity enough to enable pour off of the target fraction. these days I pull it after the crude has been homogenized into MCT at final retail strength. it sticks to the sides & bottom of the kegs which are cooled to encourage this.



Having started this endeavor it is now clear i do not know what I’ve been extracting at all. I guess the caramelizing was a good thing then. Will subzero etho leave sugars behind? Does degumming have any effect on them? I’m gonna have to look this up further. Thank you very much for making this clearer.

Edit: yeah i went a bit overboard with the solvent there. Lesson learned.

The boiling point of ethanol is 78C. The solution won’t get hotter than that until you drive off all the ethanol.


I hadn’t scrolled down far enough to see this - I just posted the same response! The solution won’t go hotter than 78 until the residual ethanol is boiled off.

are you adding solvent at decarb?
or was that just left over?

yes. sugars ARE alcohols.


above is sucrose (table sugar) . below is ethanol.
or EtOH as you’ll often see it.
by definition, it is the -OH that makes an alcohol.


you describe carmelization. I’m not sure about the chemists, but any kitchen witch will tell you that requires sugar. so taste it! notice how it forms and behaves as you cook it.

sugars are water soluble. cannabinoids are not. so you could do a liquid liquid separation on your crude to remove them before decarb I imagine. that fact is also handy when figuring out “WTF is this?” without appropriate equipment. you could also try a bioassy: eating a measured amount and noting the effect as compared to a known dose. those take constant practice :wink: and are no fun if you’re expecting an analyte at 1% target and end up with one closer to 20%. :dizzy_face:

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I was purposefully leaving some in for the previous reruns of kief. It was easier to transfer, but in the end i stopped and just leave what doesn’t come out for the next run.

transfer solvents are useful. was just concerned that somebody had taught you to add ethanol before decarbing for some bizarre reason.

as @StoneD pointed out, performing your solvent removal under vacuum will get you to the decarb step faster.

What temp are you running your ethanol extractions to generate the crude? What steps are you taking between EtOH and SPD flask?

Initially did them at -20c, overnight soak. The reruns have been at room temp between 6-20h. After I’m done with the kief its back to -20c and 10 minute soaks, just plant trim and nugs. Then ive just filtered it 2-3 times. Thought my smallest paper was 0.45 micron. Turns out it’s 1.5-3 micron. I haven’t started degumming yet. I tried cbleach once. But now it’s just filter paper. Then roto, decarb and into the spd.

Sugars from kief is a hard sell, sugars from plant matter that was within the size cutoffs to be called kief are not. Especially at room temp. I imagine that would also mean your (kief) extracts are green.

Although that definitely depends on how your kief was acquired.

It’s made through the resinator, blowing co2 through a middle bar while tumbling it. There is more plant matter in there than they thought.

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