All cannabis concentrates are not created equal. When you wander into a dispensary and browse their shatter, wax, hash, oil, live rosin, and butter products, it’s easy to let your eyes glaze over if you aren’t sure what you’re looking at. Some of it looks like hard candy, some of it looks like honey; some products come in cartridges, others come in syringes or tiny jars. But the most puzzling difference is some THC extracts are sold as “solvent-free” while others are “solventless.”
That last distinction—solvent-free versus solventless—might sound nuanced or subtle, but it’s a very important difference because while the end products might [I]look[I] similar, the processes by which the THC concentrate is extracted differ significantly, and consumers say they can actually feel a difference between them.
“I would say [solventless concentrate] is a flower high, in a dabable form,” says Blair Kralick, the COO at äkta, an artisanal hash-making company out of Carbondale, Colorado. “For me personally, it feels like it’s the most medicinal form of smoking cannabis that I’ve experienced. Especially when you smoke straight ice-water hash.”
It’s just a more organic high, Kralick says. “It feels more natural to smoke [concentrate] in a solventless form.”
Counterintuitively, solvent-free extracts are produced using one of three hydrocarbon solvents: butane, propane, or ethanol. Those gasses dissolve the resin gland heads of the actual cannabis plant material and draw the cannabinoids and terpenes from the plant matter without using extreme pressures or temperatures—essentially they dissolve the plant, and leave its resin behind.
However, all three of those conventional solvents require extra steps post-extraction to “purge” the leftover hydrocarbon solvents. If done correctly, the resin contains no residual solvents post-extraction. If it’s not done correctly, though, it can result in tainted products being sold and smoked. Or worse: Because butane propane and ethanol are such volatile gasses, labs that produce solvent-free extracts have to be very cautious about leaks and or other more explosive accidents.
Solventless extraction, by contrast, doesn’t use any solvents at any point in the process. It can either be done by hand or by using an ice-water extraction method, like äkta does. It’s completely organic and far safer for both producers and users.
“When it comes to ‘solventless’ and what the term really means, it’s not necessarily an ‘extraction,’” Kralick says. “It’s more of an agitation and feeding process where we use water as a carrier.”
He explains that the process provides complete transparency and quality to customers. When you buy an äkta extract, you know all that was used to make it was artisanal, organic cannabis from the cultivators at Hava Gardens (Boulder Weekly, “The natural way to grow,” 11/4/2021) and ice water. And because Hava’s bud is grown using enhanced “living soil” techniques, it’s healthier, more aromatic, and has higher levels of terpenes than most other commercial flower.
Kralick says the quality of Hava’s cannabis is the foundation of äkta’s extracts: They receive the flash frozen bud from Hava and partially break it up by hand to increase the available surface area. They then put that material in a 65-gallon ice water bath with a series of mesh filters underneath and the solution is agitated with paddles. In the subsequent cold, brittle state, the trichome heads will simply break off, Kralick explains.
“We take that water and we filter it through different micron screen bags,” he says. “So we have different grades of hash that will filter out.”
That process is repeated until all of the trichome heads have been collected. From there, the wet hash is scraped off of the bags, placed on trays and freeze dried for 24 to 36 hours to remove all moisture.
“What’s left are trichome heads that are trapped and basically frozen in time,” he says.
He calls it a really “old-school” technique done with newer technology and equipment. Essentially, it’s the same way that hashish has been made for thousands of years—but modernized.
Kralick admits that butane, propane, and ethanol (and even carbon dioxide) THC extraction methods do have their own benefits. The processes are much faster, require far less physical labor, and Kralick says with butane in particular you get higher terpene retention in the solvent-free product than most other extracts will retain.
But at äkta, they aren’t working with volatile gasses in their extraction lab. Nor are they going through tank after tank of hydrocarbon solvents. And even if they were using something relatively safe like carbon dioxide, Kralick says there are still risks associated with the gasses escaping or something going wrong with the system.
With ice water extraction, though, the level of risk is negligible.
“The worst thing that’s going to happen is someone’s going to get wet,” he says. “It’s definitely more environmentally friendly.”