Visitors to cannabis trade shows in recent years may have noticed the increasing number of companies touting some of the most advanced technology to be applied to the consumption of cannabis: food-grade nanoemulsions. Such nanoemulsions encapsulate a bioactive substance in a tiny particle that can more easily be absorbed by the body and combined with water or other ingredients.
In the cannabis-infused food and beverage industry, nanoemulsions are used to make active cannabinoids, such as tetrahydrocannabinol, cannabidiol, cannabigerol, and cannabinol, both water soluble and bioavailable. These paired factors make nanoemulsions a popular technology in developing cannabis-infused beverages, as well as other infused foods.
In Canada in particular, where major beverage manufacturers own large stakes among licensed cannabis producers, there is a drive to deliver cannabis beverages as a product that competes with alcoholic drinks. For such producers, nanoemulsions are one of the most effective methods not just to make cannabinoids water soluble, but also to make them metabolize more quickly.
While traditional edible cannabis products normally have an onset time of more than one hour, products infused with cannabinoid nanoemulsions may take effect within as few as 15 minutes—a huge gain for beverage producers hoping to make infused drinks as attractive to consumers as hard seltzer and other market-leading alcohol products.
Yet, some in the cannabis industry have concerns about the safety of these cannabinoid nanoemulsions in food and beverages.
“I have concerns about nanoemulsions in general,” says Rebecca White, PhD, chief technology officer for New Mexico–based Trait Biosciences, which employs glycosylation to offer a cannabinoid-infusion technology that is an alternative to nanoemulsions. Dr. White says there hasn’t been enough study of nanoparticles in food and beverages and, accordingly, food nanoparticles are inadequately regulated.
“This suite of ingredients may have unintended effects on cells and organs, particularly the digestive tract,” says Dr. White. “There are also indications that nanoparticles may enter the bloodstream and accumulate elsewhere in the body. They have been linked to inflammation, liver and kidney damage, and even heart and brain damage.”
Brad Douglass, PhD, is vice president of intellectual property and regulatory affairs for Monrovia, Calif.-based cannabis biotechnology lab the Werc Shop. He offers a largely opposing position, arguing that if all ingredients used in the creation of a nanoemulsion are classified as generally recognized as safe (GRAS) for food use and are being used within acceptable concentration limits, the nanoemulsion itself should be safe.
“If you’re using GRAS ingredients in the quantities and specifications that are permitted, that’s very unlikely to cause serious issues,” he tells Food Quality & Safety. “The term ‘nanoemulsion’ tends to throw people off, particularly the ‘nano’ prefix. When I see ‘nanoemulsion,’ I just see ‘emulsion,’ and emulsions are emulsions—you just have smaller vesicles and a more stable emulsion that permeates.”
David Julian McClements, PhD, distinguished professor in the department of food science at the University of Massachusetts Amherst, essentially concurs. Dr. McClements has published widely on the subject of nanoemulsion safety and edited a book on the science of nanoemulsions. He says, “We already consume nanoemulsions in some foods (for example, homogenized milk or soft drinks often contain nano-sized lipid droplets). If they are made from digestible oils, which they typically are, then they should be fully digested in the gastrointestinal tract, then behave like normal fat.”
Likewise, Touseef Ahmed Wani, a senior researcher at the University of Kashmir’s Department of Food Science and Technology, was the lead author (along with Dr. McClements) of a 2018 book chapter entitled “Safety of Nanoemulsions and their Regulatory Status.” He tells Food Quality & Safety, “The analysis performed regarding the safety of nanoemulsions reveals their use as safe at low concentrations. So, the use of nanoemulsions in different foods is promising.”