Where's that degumming thread, Future?

What happened to that degumming thread you said you were gonna start, @Future?

Ahem, if I may.

So let’s talk degumming.

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Hehe well man I’d imagine using the de-gumming enzyme, you would liberate some of the phosphatides into fatty acids so re-winterizing is definitely recommended. I’ve noticed when I de-gummed a fully winterized first pass, after second pass Distillation I’ve gotten good light color but the clarity was a little off (hazy). I redissolved and winterized (it appeared like nothing was there after a deep freeze and filtration thru silica), the Haze was gone after a third Distillation.

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I have only been using citric acid to degumm, about 1tsp mixed with 50mL distilled water per liter of crude. I think I had better success with more acid but haven’t confirmed. I definitely notice a difference in clarity and color compared to not using it.

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Hi. I wanted to mention that if you check out Gary List’s book in Libgen, Bleaching and Purifying Fats and Oils, he states that degumming should precede winterization, and that winterization proceeds much easier as a result.

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Hi Montanadabman, I am in MT also. I was curious if you neutralize your solution following degumming?

Regards,
Puccinia

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I proceed to do a carbon scrub before I neutralize, 1tsp MgO per liter of crude thanks to @Photon_noir in the boiling flask

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@Montanadabman @puccinia @Deleted @circus_animal Proceed with caution using carbon to decolor and acids to degum… both for the same reason: leftover acid in your crude (leached from carbon that was activated with a strong acid and incompletely washed, for example) can result in unwanted isomerization of cannabinoids.

I agree that Winterization after degumming makes sense, since degumming effectively creates fatty acids, which are some of the compounds removed during Winterization. At the very least, a cold precipitation and filtration in semi-polar solvent like ethanol:water azeotrope should be performed after any degumming. It is for this reason that I advocate for degumming directly in said semi-polar solvent.

After degum and cold precip/filter, I recommend louching (water-precipitating a milky microemulsion) the cannabinoids from the ethanolic solution, and partitioning with n-heptane or similar n-alkane to extract resin/distillate from the ethanol layer. Wash this hydrocarbon with 5% sodium bicarbonate, then pure water, then NaCl brine… then dry the solution with anhydrous sodium sulfate and decant. This will neutralize, decolor, purify, and dry the resin in alkane solution. Then evaporate to acquire cannabinoids for use or redistillation.

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Here is a way to test your winterized crude to see how well it did during the dewax that you do use. Disolve an ounce or less in pure methanol of the dewaxed product. I use about a 4 to 1 ratio at least. Add water at 10-20% ratio. Place in front of a fan in an open evap dish.

When it evaps off any waxes present will tend to clump up and form on the evap dish walls and such. It will form hard enough clumps that it takes a small all metal pick to pry it off the dish.

I have seen significant wax form this way after dewaxing otherwise. There simply is no step it seems that is a perfect solution in seperations but each little one adds up in purity. It is good to know from this test how you are doing. I pick a lot out manually lolz just to really get it clean but mostly the extract can be washed off the hardened wax pretty easy too.

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Summit enzyme has an extra PL that doesn’t do much for our process, it cleaves the phosphatide that was already separated from the FAs. In that regard it is not necessarily an inferior product but is probably originally meant for a different type of degumming than what we require.

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How much different is your sop for the critic acid vs colombo enzyme

I’m not sure, I normally add 50 mL distilled water with 1 tsp citric acid to 1 liter of crude at 65c and mix for 5-10 minutes.

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@Photon_noir will you please explain the louching process in more detail? It’s not as simple as adding water until the thc is no longer soluble in the ethanol is it?

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Yes. Yes, it is. I have explained it elsewhere, but the idea is just to add excess water (i.e. more than 5%) to the ethanol until it drops the majority of your cannabinoids. It doesn’t take much… maybe 10% by volume. You then just add a non-polar layer to absorb the louched cannabinoids from the lower aqueous ethanol layer. You can tell if it needs more water by adding some water through your non-polar layer after it has absorbed the milk from the lower aqueous ethanol layer, to see if more milk forms. Usually it won’t.

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So an SOP for this might look like:

-Add distilled water, more than 5% of volume of the ethenol.
-Add 1 tsp citric acid to 1 liter of expected crude at 65c
-mix for 5-10 minutes.
-put into sep funnel,
-Drain off heavier water.
You can tell if it needs more water by adding some >water through your non-polar layer after it has >absorbed the milk from the lower aqueous ethanol >layer, if more milk forms. Usually it won’t.

No and no. There is no standard operating procedure because the inputs will always vary. Not everyone has the same concentration of resin in their ethanol, nor the same terpenes. It may be an OP, but never a SOP!

The other “no” is this procedure is missing some key elements… like time for citric or oxalic acid or enzyme to work… and when did you add a non-polar? Also, why would you precipitate/louche cannabinoids before adding the degumming agent? It will work better if everything is in solution.
Maybe predissolve the degumming agent in as little water as possible (probably only a gram of acid [or less of enzyme] per liter of 190p ethanol:resin solution is fine), then add that water to the stirred solution, heated to 40-45°C. Add it slowly to avoid louching as much as possible, but a little louching is okay for now. Let this react for at least an hour at temperature with stirring (cap the jar to keep excess air out). Now Winterize the solution (chill to -40 or less and filter fine solids while cold)… if it was at all louched at room or rxn temperature, you need to add some clean 200p or 190p ethanol to redissolve any crashed resin prior to Winterization! Once Winterized, then you can louche the resin out with water and partition with non-polar to extract said resin, then drain off the acidulated aqueous ethanol. Wash the non-polar at least twice with distilled water, brine, or both. Make sure the NP solvent is totally transparent (no haze or cloudiness) before final separation and evaporating the solvent… you can even add some anhydrous drying salt like sodium or magnesium sulfate to help dry the NP.

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Do you ever have to rebalance the PH when doing citric acid degumming only?

Can someone elaborate on the soaking of citric acid? what do you use? and when do you add the water?

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@lefties.cannabis @lotus8565

Workers use citric acid to “degum” distillate or crude resin intended for making distillate. There are several ways to employ it, and all require a bit of water to disassociate the acid… i.e. make it acidic by letting it ionize into H+ (actually H3O+ “hydronium” cations in water) and negatively charged citric conjugate base anions.

Before you begin working with any acid or base, you should measure the starting pH of your hydrated (water-containing) resin solution. To do this, use Hydrion pH paper (the thin roll of yellow paper sold packed in foil in a clear plastic “tape” dispenser with a pH 1.0 to 14.0 color key on it) to test the pH of your room temperature 190 proof ethanol:cannabinoid solution. Write down the starting pH!

In all likelihood, it will be somewhat acidic, but close to neutral. This is mainly due to a natural property of ethanol; it reads slightly acidic because of the strong hydrogen bonding with water. Depending on the resin/distillate content (decarbed or not, terpenols, etc.) and concentration, the pH of the ethanol:resin solution may read between 5 and 7.

The easiest way to use citric to degum is to dissolve the distillate or crude into 190 proof ethanol (95% ethanol with 5% water in an “azeotrope”), the same as is done for Winterization, then dissolve some citric acid into it, little by little with stirring at 25 to 30°C. You do not need or want any excess water in this mixture! The amount of citric acid used is small; since it is acting as a catalyst, it does not get used up, but keeps regenerating after each reaction (rxn) to break apart the phospholipids (aka: gums, phosphatides, lecithin triglycerides).

However, especially in crude, some of the citric does get used up in a complexation (aka chelation) rxn with metal atoms and/or the phosphorous compounds, so you can add small amounts of the solid citric acid to the liquid with stirring, waiting each time for it to dissolve/disappear, just until it stops dissolving, leaving a small amount of solid citric acid in the bottom of the mixing vessel or swirling about as you stir it.

In especially gummy material, you will likely see precipitating veg oil flocculant solid “clouds or puffs” swirling in the liquid… they come from the rxn of citric acid with the phosphatide triglyceride gum, as the triglycerides break apart into separate fatty acid and glycolated phospholipid chains. This just means the rxn is working, and that you have a visibly large amount of gum to react with. Do not confuse these with the solid citric acid crystals (xtals). They look like fluffy clouds, while the citric xtals look like grains of sand. You are done adding citric acid when you either see solid citric acid xtals that refuse to dissolve or if you see no more of the flocculant precipitate forming.

Caveat & Caution: If you are trying to retain all CBD or working with high CBD crude or distillate (like from hemp), it is best to avoid the combination of acid and heat (even just above 30°C) at all times. Otherwise you may end up isomerizing your CBD to Δ8-THC.

If there is visible solid flocculant in the room temperature liquid, go ahead and filter it out, now, using vacuum or pressure filtration as you would for Winterization. It is extremely fine sediment, so it really helps to use a 3-dimensional matrix of filter media over your standard 2D filter paper. This can be a cake of filter aid, like fine laboratory grade silica (e.g. 220 mesh sand) or calcined diatomaceous earth, such as Celite brand (make sure it is documented to have a neutral pH in water… or see ☆ below for this special case). You can also use glass wool or (my favorite) pure cotton.

The next, often mistakenly skipped, step is to fully precipitate the flocculant by chilling. This is done exactly the same way you would perform Winterization. After all, you just turned the gums mostly into the very same sort of vegetable oil you would normally Winterize to remove. Chill and filter in small aliquots (parts of the whole liquid body… in order to keep it all as cold as possible or practical during filtration) the same way you filtered above, using filter aid.

Now it is time to remove or neutralize the citric acid. Normally, I recommend a liquid/liquid partition extraction of the cannabinoids from the ethanol by adding excess water to louche (i.e. a milky microemulsion) the resin from the ethanol, then extracting the resin with a layer of n-alkane (hydrocarbon) like n-pentane, n-heptane, etc. Separate the now resin-laden alkane from the now depleted aqueous ethanol, and wash the alkane with some salty water. However, this is not always an option for my clients, nor is it always necessary or desirable, and I would like to introduce a new method…

☆This is speculation, as I have not tried it yet, but I am a pretty darn good “guesser”. :wink: I am fairly certain we can neutralize and possibly even sequester (lock down) the citric acid by using an alkaline Celite for filter media, but I do not know what makes them all alkaline; there are many types, so the salt products are unknown to me. If you want to use one, talk to Sambo Creeck (sic) Filtration about Celite filter aid options that are alkalinized with magnesium.

However, I have an idea that plays well with stuff we already use: We should be able to simultaneously neutralize, sequester, and filter out any cold-ethanol-insoluble-but-still-mobile magnesium citrate salt particles by simply adding a layer of the less expensive varieties of magnesium silicate on top of your filter aid of choice from before. Magnesium silicate, aka: MagSil, is now a very commonly available chromatography stationary phase medium known as MagSil PR for pesticide remediation in the cannabis industry… just ask @Shadownaught …but you don’t need the specially calcined PR type for this, so you may be able to get some less expensive back stock of non-PR magsil. The best part about this is the magnesium citrate salt, even if some slips through the cold filtration, is already alkaline, not acidic, and has a high decomposition temperature of 200°C… and although that is certainly in the range of our distillation process, the decomposition products are magnesium carbonate and eventually magnesium oxide. This means that no matter what happens, the products of this procedure are not going to hurt and may even help your distillation process! :grinning:

Finally, use the Hydrion paper to test the pH of your degummed ethanol:cannabinoid solution. The pH should be the same as it was when you started, when the paper warms to room temperature after about 1 minute… unless some magnesium citrate salt made it through, which will make it more alkaline… hopefully a nice neutral 7.
However, just in case it is acidic (i.e. ONLY if it has lower pH than it started with), let the liquid warm to room temperature in a covered vessel (to keep out water condensation from the air), then fully stir in small pinches of magnesium oxide (MgO) at a time to bring the pH to 7.

For the record, this is the first and only time I have ever recommended any pH adjustment outside of pesticide remediation… and I am really just hoping to neutralize the citric degumming acid. I am not shooting for acid or alkaline conditions at all.

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ah-ha! here is the info i was looking for. thank you :slight_smile:

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I’m curious, has anyone tried straight water degumming? I found a few articles on this but this pdf is probably the most straightfoward. The water degumming process starts on page 9.

Water Degumming

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