In our final post, we touched on the cultural and industry shifts shaking up the cannabis business – slash society at big – and how uncomplicated it is to get caught up in that dizzying whirlwind of “trendy tricks” and misinformation if you do not ground your self in the time-honored scientific fundamentals. Extraction, distillation, vacuum distillation. Humans have been calling on these approaches to separate and isolate desirables from undesirables because ancient occasions. So nowadays, let’s dig into the cannabis solvents that make these processes attainable.
Solvents, solvents, solvents.
Just after gathering the plant material, you want anything to draw out the desirable elements – mostly cannabinoids (CBD/THC), but some want these terpenes for aroma/flavor, as well. This is exactly where you have got lots of solutions. There is undoubtedly no dearth of creativity when it comes to solvents for cannabis extraction and distillation. Do a speedy Google search and you will discover tons of solvent testimonials, not to mention a handful of inventive combinations and approaches invented by extremely committed “garage scientists.” (Seriously, some of these guys and gals genuinely know their chemistry, and the rigs they’ve MacGyvered are genuinely impressive.)
A handful of solvents operate just fine, some not so good, some superior than others… and, hey, 3 cheers for innovation, suitable? But if you want a trustworthy extraction method, there are 3 cannabis solvents that top rated quite significantly every single skilled extractor’s list.
We’ll hit on the 1st a single nowadays, and the other two in upcoming weblog posts.
C2H6O: Secure, helpful, classic.
Some would argue that ethanol [C2H6O] deserves the “universal solvent” title even extra than our superior buddy H2O. This is due to the fact ethanol can dissolve each polar (hydrophilic) and nonpolar (hydrophobic/lipophilic) substances. It is quite significantly a solvent that invites every person to the celebration. Really inclusive, that ethanol molecule is.
- Ethanol’s polar hydroxyl [OH] group – with oxygen’s higher electronegativity permitting hydrogen bonding to take location with other molecules – will dissolve hydrophilic (water-loving) compounds like chlorophyll, pigments and tannins.
- Ethanol’s nonpolar ethyl [C2H5] group, a.k.a. its “hydrocarbon tail,” functions with the hydrophobic (water-fearing) elements like plant waxes/lipids, oils, cannabinoids, terpenes (aroma/flavor) and any other substance (except for plant fiber) that is present inside or on the outdoors of the plant. (And, of course, it is these cannabinoids/terps we’re soon after.)
STEP A single: Extract the desirables.
Now, a lot of folks like utilizing ethanol for cannabis extraction due to the fact
1) it does not demand higher stress like the other two well-known solvents (supercritical CO2 and butane, which we’ll speak extra about later) and is for that reason safer, and
two) it produces a complete-spectrum concentrate*. So, not only are you drawing out the significant-name cannabinoids (CBD/THC) and terps, but you are also finding the elements that are present in significantly smaller sized concentrations – some of which haven’t been studied or even found however, but could possibly play into the interactive synergy involving marijuana compounds. This has been coined the entourage impact**, and quite a few strongly think that it is this holistic (“full-spectrum”) interplay involving plant components that contributes to an enhanced therapeutic knowledge.
* This is if you are utilizing the “full-extract” approach with hot/warm ethanol. Undertaking a “quick wash” with cold ethanol is a entire other ballgame due to the fact, due to shorter extraction time and reduce (freezing) temperatures, the solvent will not choose up practically as quite a few compounds. Extraction is a double-edged sword – the longer and extra aggressive the method, the extra each desirable and undesirable compounds will make it into the extract. So, a much less intense extraction will get you a weaker concentrate, but you will not want a hefty distillation method to isolate/refine the item. A longer and stronger extraction, on the other hand, calls for a longer, stronger distillation. Therefore, “double-edged sword.”Check out this report on Culinary Solvent for a comparison involving the “full extract cannabis oil” (FECO) and “quick wash with ethanol” (QWET) approaches.
** The entourage impact has been finding a lot of focus lately, and for superior explanation. Really fascinating stuff. Leafly has a excellent study on the entourage impact and entire-plant medicine, which includes a good graphic of cannabinoids and terpenes with their person and synergistic properties and added benefits. Surely verify it out if you have the time and interest. (I did, and I’m undoubtedly superior for it.)
STEP TWO: Winterize the concentrate.
Just after extraction, you will want to winterize the concentrate to take away these undesirable lipids/waxes that the C2H5 ethyl group (nonpolar hydrocarbon tail) picked up. You do this by 1st dissolving the extract in some added warm ethanol, and then cooling the option to a temperature that is low sufficient to precipitate (solidify) and filter off the undesirable fats.
STEP 3: Distill the concentrate.
Try to remember, our finish game right here is solvent-absolutely free extract oil. You do this by way of distillation (“purging”), the evaporation of solvents. Ethanol boils off at about 78°C at atmospheric stress. If you pull a complete vacuum (assuming you can pull -28.5”Hg), it reduces ethanol’s boiling point to 12.8°C, which is properly beneath space temperature. These vacuum situations safeguard against item degradation due to a substantial reduction in heat exposure (thermal decomposition) and oxygen exposure (oxidation). You can use a rotary evaporator (roto-vap) or vacuum distillation apparatus to take away/reclaim the ethanol, yielding solvent-absolutely free extract oil. (You can also achieve this by heating your option in a hot water bath, but you will not be in a position to reclaim the evaporated ethanol.)
Note: If you are extracting with cryogenic ethanol (about -70°C) alternatively of warm ethanol, the winterization step is integrated. So, soon after extracting the desirable oils from the plant matter, you can go suitable to filtering (utilizing anything like activated carbon to take away what ever chlorophyll and other pigments that produced it by way of) and removing/reclaiming the ethanol by way of distillation. Even so, because this is a frozen extraction, and temperature plays such a crucial function in solvency, not as quite a few elements (desirable nor undesirable) will be drawn out of the cannabis.
So, to recap:
Since ethanol has each polar and nonpolar components (and for that reason dissolves each hydrophilic and hydrophobic molecules), and it does not demand a higher-stress extraction, it is viewed as (by most) to be the safest and most helpful cannabis solvent in the game. That getting mentioned, it is undoubtedly not the only alternative. Keep tuned for our subsequent post, exactly where we’ll continue our discussion on cannabis workflows with a appear at two other well-known solvents: supercritical CO2 and butane.
Can not wait till the subsequent Cannabis weblog? Get the entire kit and caboodle by going to our Cannabis Resource Hub to access extra details on ethanol extractions, the temperature manage gear you will want for processing cannabis, existing promotional pricing, and our whitepaper/weedpaper, The Cannabis Workflow and the Value of Temperature Handle.