Leading extraction scientists and researchers from the cannabis industry—John A. MacKay, Synergistic Technologies Associates and Brian C. Smith, Big Sur Scientific—participate in this round-table discussion series on extraction. This month they discuss which techniques or methods are the most successful for cannabis extraction.
Which technique or method do you think is the most successful for cannabis extraction?
John A. MacKay: The most successful method is to start with the end in the beginning. I have a minimum of five types of extraction and separation in the manufacturing process. Let’s consider eggs as a word picture. If you have a flat pan with a small lip around the edge, you can make fried eggs. The number depends on the size of the pan. You can also make scrambled eggs as long as you are careful of the number and additives such as onions, bacon, cheese, and so forth. If you are aware of the size of the pan, you could also make an omelet. However, you are not going to make a boiled egg or a poached egg. There are many techniques for doing botanical-centric extractions and separations. They are all possible depending on the ingredients that are needed for your formulations.
Brian Smith: I tend to prefer ethanol extraction. It is much safer to use than hydrocarbon solvents, and the equipment is less expensive and easier to run than supercritical carbon dioxide setups. Another advantage of ethanol is that typically one winterizes crude oils by dissolving them in ethanol. Use of ethanol as the original solvent means you already have that step covered.
I realize that different solvents give crude oils with different cannabinoid and terpene profiles. But many manufacturers end up making distillate to put in vape pens. Distillates contain very little terpenes and are mostly tetrahydrocannabinol (THC), so the nature of the extraction solvent used has little effect on the composition of the distillate in my experience.
Look for part III of "Ask the Experts: Extraction" in our September 2019 newsletter. Part II of our series on cultivation will appear in July and Part III of the series on analytical methods/cannabis testing will appear in August.