Talking Extraction: Continuous-Flow Extraction, Quality Control, Challenges, and More

As the cannabis industry shifts towards more regulations and safety standards, it’s essential for companies to produce reliable and reproducible materials for their consumer products. Extraction companies across the world will be tasked with processing materials accurately and consistently. We recently spoke with Dr. Steven Splinter, CTO and founder of Radient Technologies, Inc., to find out how his company is tackling some of the issues facing extractors. Here, Dr. Splinter shares some insight into how his company handles cannabis extraction, quality control, challenges, and more.

How did you first get involved in cannabis extraction?
Dr. Steven Splinter: I founded Radient in 2001-and believe me I had no idea back then that I would one day be working with cannabis! The company began as a botanical extraction and ingredient manufacturer, but it wasn’t until 2016, after the government of Canada began the process of legalizing cannabis federally, that we began to look seriously at working with cannabis. We recognized that with these favorable changes coming with respect to cannabis legislation, that there was going to be a very significant need to extract cannabinoids with a higher efficiency. We saw the opportunity to capitalize on the industry’s desire to partner with a reputable extraction expert that was able to offer product manufacturing under strict quality systems, while possessing the capacity necessary to meet demand. So, here we are in 2020, and Radient has pivoted from a botanical extraction and ingredient manufacturer to a cannabis extraction and ingredient manufacturer, because the demand has been so great.

How does your extraction technology differ from other extraction methods on the market? Are you using any other extraction methods?
Splinter: There are a number of ways that Radient’s extraction technology differs from other existing methods. First, our method is a continuous-flow extraction process rather than the industry standard, which is batch processing. This allows us to process much greater volumes of raw material without having to stop and restart material flows, and also means we can scale-up to these higher throughputs very easily, without the need for costly additional machine time and human labor. It also allows us to have precise control over extraction time and temperature, so that the negative effects typically associated with heating are minimized. Also, because the material is extracted at the same time and temperature, we can achieve better extraction efficiency and recover more cannabinoids from the biomass-up to 99%, whereas comparative methods achieve 70–80% recovery of cannabinoids.

Second, our method avoids additional purification steps such as winterization, which takes 24 hours or more to complete and is required by other extraction processes to remove undesirable elements from the extract (fats, waxes, pigments, and so on). This allows us to maintain high overall process efficiency, because we avoid additional cannabinoid losses that can happen during these additional purification steps. In addition, we can minimize the losses of other components such as terpenes and therefore maintain more of the full plant profile.

What kind of quality control and testing measures are used in your manufacturing facilities?
Splinter: We are Health Canada approved and good manufacturing practice (GMP) compliant, so the quality control and testing measures are very high-level. We have well-established quality systems including on-site quality control laboratories.  Even the level of security we have is very high-level and very thorough. Making ingredients and products that are safe, consistent, and properly labelled is extremely important to us.

What is the biggest challenge facing cannabis processors and manufacturers that want to do their own extractions?
Splinter: I would say that there are three very important considerations a processor must consider when deciding to do their own extractions:

• the extraction efficiency that can be expected from the chosen method (defined as the percentage of available cannabinoids that are recovered through the entire process);

• the ability to scale up to meet demand; and

• the ability to repeatedly achieve optimal product quality to ensure product safety and consistency.

Anyone can extract at relatively small scale by purchasing the appropriate equipment-which is the case with, for example, supercritical CO₂, and other conventional solvent extraction methods. However, often the extraction efficiencies for those types of equipment are not great. Also, when you want to scale up to much larger quantities, you need to keep purchasing more equipment to scale up, which becomes expensive. These methods also require repeatedly stopping and restarting material flows, which is time consuming and laborious-you need to have people there to monitor this process. Another drawback of these methods is that it is difficult to ensure that extracts are consistent across batches, so consistent potency of the product is difficult to guarantee.  

Our technology can easily scale-up to processing much larger quantities because it is a continuous-flow process, meaning there is no stopping and restarting of material flows. This allows us to process much larger throughputs, much faster, with minimal human labor or intervention. It also simplifies the GMP requirements, reducing the overall quality assurance costs. Finally, we can achieve much greater extraction efficiency (up to 99%) from the biomass, and so can ensure optimal economics.

Your company has partnered with several others such as The Edlong Corporation and Aurora Cannabis to create CBD products. Can you discuss your role in those partnerships? What advice do you have for other companies that are looking for extraction partners?
Splinter: Our partnership with Aurora is pretty straightforward: we are taking their raw cannabis and hemp materials and producing extracts and products from those materials. With Edlong, we are collaborating to develop unique CBD ingredients for the food, beverage, and pet food industries.

As for advice, explore within your network-you never know who might be venturing into cannabis next-all kinds of industries from pharma, to food and beverages, cosmetics, even pet food companies are now incorporating these ingredients into their products. When choosing an extraction partner, look for a reputable extraction expert with full quality systems, who has the capacity to meet your future demands.

Do you foresee cannabinoid products expanding in the future? Will there be CBN and CBG products?
Splinter: In short, yes. The more research is done on the benefits of these lesser known and lesser understood cannabinoids, the more we will begin to see the demand for these products start to increase. CBN, for example, has been shown to work well as a sleep aid, but it has also been shown to help regulate the immune system, and relieve the pain associated with inflammation.

What are the next steps in your extraction research?
Splinter: We have been working on a number of specialty ingredients that improve the taste and smell of cannabinoids while also maintaining their therapeutic benefits. This will be something we explore in more depth with our new collaborative partners, such as Edlong. We also continue to develop various cannabinoid formulations with improved properties, such as being water soluble or water dispersible, and which also have improved stability for longer shelf life.

How to Cite This Article

M. L'Heureux, Cannabis Science and Technology3(1), 16-17 (2020).

Editor's note: The print version of this article was an excerpt of the full interview presented here.