What is distillate?
Honey oil, clear, distillate; the oily substance that can be extracted from cannabis goes by many names and is largely misunderstood, even by those in the industry. Distillate is only one form of extract that can be derived from the plant, with others going by different names like: shatter, wax, and live resin. The process for extracting these substances differs, although the general methodology is the same; introduce solvent to the plant material in order to strip it of its cannabinoids and terpenes.
Traditionally, there are three main forms of solvent extraction: CO2, butane/heptane, and ethanol. Each has its own positives and negatives, and different manufacturers across the cannabis industry will claim that their method is best. As a primary introduction to the differences of each method, I recommend checking out Mike May’s article, “The Best Cannabis Extraction Methods for Marijuana Concentrates” on annalyticalcannabis.com (linked below).
Winterized Crude Oil
As mentioned previously, each solvent extraction method can yield very different results. For example, through butane and CO2 extraction, a manufacturer can procure isolates with higher cannabinoid contents than the distillate made available through ethanol extraction. Ethanol extraction however, is very effective in stripping the plant material of its cannabinoids and terpenes, while leaving most of the chlorophyll molecules on the plant. Extraction data has shown ethanol can yield more extract per pound of raw biomass than other methods (as high as 95% efficiency).
Extract that contains chlorophyll can be incredibly harsh when smoked, so higher quality extraction processes aim to keep the chlorophyll out. The process of removing the chlorophyll and other plant lipids is called winterization.
Once winterization has occurred, the solvent/cannabis mixture (often referred to as tincture), must be stripped of its solvents. This is performed using a kind of evaporator, like a rotary evaporator, or more specialized equipment. What is left is a dark crude oil that contains the cannabinoids, plant terpenes, as well as some remaining chlorophyll and other plant waxes.
Distillation
The winterized crude oil must go through the process of decarboxylation, then is ready for distillation. Currently, the industry standard for distillation is using fractional distillation equipment. This equipment introduces the crude oil to varying levels of heat in order to separate into three main fractions: distillate, terpenes, and the residual chlorophyll and waxes.
If executed correctly, the resulting distillate should be very high in cannabinoid potency (ideally over 90%). Depending on the desired result, the distillate may go through additional processing that will result in other, even more potent extracts such as wax, shatter, sauce, etc. These potent extracts are what is often referred to as isolates, and can yield a potency over 95% of a specific cannabinoid (like THC or CBD).