In our final post, we touched on the cultural and market place shifts shaking up the cannabis market – slash society at big – and how quick 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 techniques to separate and isolate desirables from undesirables because ancient instances. So nowadays, let’s dig into the cannabis solvents that make these processes attainable.
Solvents, solvents, solvents.
Immediately 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 choices. There is surely no dearth of creativity when it comes to solvents for cannabis extraction and distillation. Do a rapid Google search and you will uncover tons of solvent testimonials, not to mention a handful of inventive combinations and techniques invented by quite committed “garage scientists.” (Seriously, some of these guys and gals seriously know their chemistry, and the rigs they’ve MacGyvered are actually impressive.)
A handful of solvents operate just fine, some not so good, some far better than others… and, hey, 3 cheers for innovation, ideal? But if you want a trustworthy extraction approach, there are 3 cannabis solvents that major quite considerably each knowledgeable extractor’s list.
We’ll hit on the 1st a single nowadays, and the other two in upcoming weblog posts.
C2H6O: Protected, productive, classic.
Some would argue that ethanol [C2H6O] deserves the “universal solvent” title even extra than our great pal H2O. This is simply because ethanol can dissolve each polar (hydrophilic) and nonpolar (hydrophobic/lipophilic) substances. It is quite considerably 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 enabling hydrogen bonding to take spot 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,” operates 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 just after.)
STEP A single: Extract the desirables.
Now, a lot of individuals like making use of ethanol for cannabis extraction simply because
1) it does not need 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 large-name cannabinoids (CBD/THC) and terps, but you are also finding the elements that are present in considerably smaller sized concentrations – some of which haven’t been studied or even found however, but could possibly play into the interactive synergy in between marijuana compounds. This has been coined the entourage impact**, and several strongly think that it is this holistic (“full-spectrum”) interplay in between plant components that contributes to an enhanced therapeutic encounter.
* This is if you are making use of the “full-extract” system with hot/warm ethanol. Performing a “quick wash” with cold ethanol is a complete other ballgame simply because, due to shorter extraction time and reduce (freezing) temperatures, the solvent will not choose up practically as several compounds. Extraction is a double-edged sword – the longer and extra aggressive the approach, the extra each desirable and undesirable compounds will make it into the extract. So, a significantly less intense extraction will get you a weaker concentrate, but you will not want a hefty distillation approach to isolate/refine the solution. A longer and stronger extraction, on the other hand, calls for a longer, stronger distillation. Therefore, “double-edged sword.”Check out this write-up on Culinary Solvent for a comparison in between the “full extract cannabis oil” (FECO) and “quick wash with ethanol” (QWET) techniques.
** The entourage impact has been finding a lot of focus lately, and for great purpose. Really intriguing stuff. Leafly has a wonderful study on the entourage impact and complete-plant medicine, such as a good graphic of cannabinoids and terpenes with their person and synergistic properties and advantages. Certainly verify it out if you have the time and interest. (I did, and I’m surely far better for it.)
STEP TWO: Winterize the concentrate.
Immediately 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 further warm ethanol, and then cooling the answer to a temperature that is low sufficient to precipitate (solidify) and filter off the undesirable fats.
STEP 3: Distill the concentrate.
Don’t forget, our finish game right here is solvent-totally 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 nicely under space temperature. These vacuum situations safeguard against solution degradation due to a considerable 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-totally free extract oil. (You can also achieve this by heating your answer 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) rather of warm ethanol, the winterization step is incorporated. So, just after extracting the desirable oils from the plant matter, you can go ideal to filtering (making use of 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 means of distillation. Nonetheless, because this is a frozen extraction, and temperature plays such a crucial function in solvency, not as several elements (desirable nor undesirable) will be drawn out of the cannabis.
So, to recap:
Simply because ethanol has each polar and nonpolar components (and for that reason dissolves each hydrophilic and hydrophobic molecules), and it does not need a higher-stress extraction, it is regarded (by most) to be the safest and most productive cannabis solvent in the game. That getting stated, it is surely not the only alternative. Remain 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.
Cannot wait till the subsequent Cannabis weblog? Get the complete kit and caboodle by going to our Cannabis Resource Hub to access extra details on ethanol extractions, the temperature handle gear you will want for processing cannabis, existing promotional pricing, and our whitepaper/weedpaper, The Cannabis Workflow and the Value of Temperature Manage.