Recent Advances in Cannabis Emulsion Science

Cannabis oils are just that, oils. Their fatty, viscous nature is key to ensuring their cannabinoids are absorbed by the body’s digestive system. So how is it that certain extractors can produce cannabis-infused, water-based beverages, then? If these products aren’t oils, how can their cannabinoids be absorbed by the body?

The answer is emulsion. The emulsification process effectively breaks down cannabinoid oils into billions of very small droplets that can then be suspended within such products without the two separating. Emulsification also has the benefit of increasing the available surface area of a cannabis oil sample, which can lead to a higher bioavailability and faster onset of effects.

Two years ago, Dr. Harold Han, founder and chief science officer at the Oakland-based infusion technology company Vertosa, gave Analytical Cannabis readers an inside look at the developments that had been occurring within the cannabis emulsification space.

We caught up with Han once more to ask him how cannabis emulsions have advanced in the intervening years.

New pharmacokinetics data

Pharmacokinetic (PK) studies are an important tool in cannabis emulsion research, as they are essential to understanding how bioactive compounds are absorbed and metabolized by the body.

Back in 2021, Colorado State University and Caliper Foods had just published an important new PK study examining five different oral CBD preparations. It found that CBD emulsions are absorbed significantly faster by the body than CBD tinctures or traditional isolates.

Cannabinoid gummies, like most edible products, are usually slow to make their effects felt. Using cannabis emulsions can speed up this process, Han says, though there is still a lot to be learned about cannabinoid emulsions in gummy matrices. Vertosa recently conducted its own PK study looking at how the body reacts to THC gummies made with Vertosa’s own emulsion system.

“A lot of clients validated these [fast-acting] effects but we didn't know how quickly, or what was happening in the blood,” Han explained. “So we took a deeper look, measuring six people in our lab and comparing emulsion gummies with regular [ones].”

“From the data, I can share with you that our gummy PK on THC feels like you’re smoking a joint. It’s like five minutes and you have peaked [THC concentration-wise] and then you slowly go down. That is like a smoking effect, but it doesn’t feel like smoking,” Han said.

It isn’t just THC and CBD that are attracting the attention of emulsion scientists. Through Vertosa’s partnership with UMass Amherst, the team are also working to better understand the nutritional applications and performance of cannabigerol (CBG) emulsions.

“We were thinking you take the same [emulsion] formula, just switch THC to CBG. We thought it should be the same – it’s a carrier, it should deliver different APIs [active pharmaceutical ingredients] in the same way,” Han said, recalling the early days of the research. “But actually, CBG absorbs [in a manner] a whole lot different from THC. We see a whole different absorption profile.”

Improving the performance of cannabis powder

Cannabis powder is often marketed as an alternative to traditional cannabis edibles. Instead of baking pungent cannabis flower into a brownie or some other sweet treat, a customer can dissolve some water-soluble, flavorless cannabis powder into a glass of water and ingest their cannabinoids that way.

Cannabis powder is not a new thing, but emulsion science is key to creating a good cannabis powder product, and advances in emulsion science are helping to improve the performance of the products that are on offer to consumers.

“When powder dissolves in water, the cannabinoids are released into the water in small droplets. What is the size [of these droplets]? We tested a lot of powder from the market and the size of the droplets released in the water is very hard to control. They are 1,000 nanometers or 2,000 nanometers – huge droplets,” Han said.

“Because we are an emulsion company, we use the emulsion as a starting material and plate that emulsion onto a powder base,” Han explained. “This powder, now, if you put it into water, the emulsion doesn’t get destroyed or changed. It will detach from the powder base and flow into the water. So, essentially, you are drinking our emulsion in the beverage.”

Using this approach, it is possible for cannabis powder to have more consistent performance in terms of onset time and absorption. “If the emulsion onset time is 15 minutes, then the powder onset is 15 minutes,” Han quipped.

Towards emulsion-grade distillate

Oddly enough, one of the most recent steps forward in cannabis emulsion science has involved almost shifting focus away from the end products that are made with cannabis emulsions, and towards the extracts and distillates that product manufacturers are working with.

“Cannabis is an agricultural plant and it’s seasonal. How you handle it, how you extract it, all of this affects the flavor,” Han explained. “Extracted oil may taste good when you are doing a vape cartridge or putting it in a gummy – that doesn’t affect that flavor. But if you cut into billions of smaller droplets in an emulsion, you sometimes intensify whatever terpenes or flavonoids are there. Those flavors have an impact.”

To begin to address this, Vertosa is currently engaged in collaboration with several partners in the extraction and distillation sector to evaluate how distillate is handled and what might make the difference between distillate that could be considered “emulsion-grade” and distillate that might leave behind an unpleasant aftertaste.

“We are working with a couple of partners to just go back to the drawing board,” Han said. “From the strain, to extraction, to distillation, what are the steps needed for emulsion-grade distillate to say, ‘if you do these steps, we guarantee that this is good for emulsion and when put into a beverage, it has no weedy taste?’”

This article originally appeared in the Analytical Cannabis - January 2023 Digest.