Maybe you have heard about dabs, and someone may have explained how concentrates are made, but perhaps you’re still a little hazy on the specifics? In our series dedicated to introducing the new toker to the beautiful new world of cannabis, today we’ll be taking a look at the different types of marijuana concentrates and how they are made.
Think of cannabis concentrates as an isolation or separation of the beneficial cannabis compounds from the plant – the goal being a pure, therapeutic combination of cannabinoids and terpenes. In layman’s terms, this means your final product is 90-100% THC, whereas cannabis flower is more like 15-20% THC. This concentration of beneficial compounds allows the user to consume a far smaller volume to achieve the same effects. This article outlines the different extraction techniques used to make cannabis concentrates.
Cannabis concentrates can be divided into two main categories: solvent and solventless extractions. A solvent is a substance that dissolves a solid, resulting in a liquid solution. When we talk about cannabis concentrates, popular solvents include butane, propane, CO2, and alcohol. Although water is technically a solvent, ice-water extractions are typically classified as a non-solvent extraction in the cannabis world. Solventless extractions do not introduce any foreign substances (except for water).
Many people refer to concentrates by their consistency, i.e. shatter, budder or wax. However, the consistency of a concentrate alone does not indicate which extraction technique was used. The same extraction method can deliver a variety of final-product consistencies. The method of extraction and the starting material is far more important than the concentrate’s final consistency, as there are several variables that manipulate the consistency; some are in control of the extraction artist, while others are not.
The reason for this distinction is that extraction practices dictate the healthiness of the concentrate, while the consistency is largely preference-based from a consumer standpoint. For instance, many people debate shatter vs. budder; but shatter can be converted to budder by simply whipping the concentrate on a hot plate. Furthermore, you can derive a buttery consistency via BHO, PHO, and CO2 extraction. It’s the solvent (if any) and starting material that matters. Starting material can range from dry trim to cured buds to fresh frozen whole plants. It’s your responsibility as a thoughtful consumer to inquire from your budtender about the starting material and extraction process used in your favorite concentrate.
Solvent-based extractions typically produce concentrates that are known as oil. If made properly, this means the concentrate will be free of plant matter (also known as contamination). These oils will melt and vaporize to nothing – meaning very minimal residue will remain on the nail if dabbed, for instance. The consistency of solvent-based cannabis concentrates varies greatly based on a few factors: strain of cannabis, growing conditions, curing environment, extraction technique, the solvent used, purging process and equipment used all play a role in the final product.
Cannabis concentrate derived from a butane-based extraction is referred to as Butane Hash Oil or BHO for short. BHO is by far the most popular concentrate of late as a result of its potency and varying consistencies; shatter, budder, snap n’ pull, and sugar can all be derived from butane extraction. Although dangerous to make at home, sophisticated machinery has made commercial production safe and effective. BHO should be produced by a reputable extractor who understands how to properly purge each run to avoid unpleasant aftertaste or harsh residual butane.
Perhaps the best analogy for how it works is an espresso machine: as the water passes through the puck of ground coffee beans it strips them of their oils (which contain the caffeine, flavor, and aroma) into a filtered, highly concentrated solution. For cannabis, the extractor places plant material in a column with a filtration screen at the end, and as the butane passes through the column it strips the plant material of its cannabinoids and terpenes.
The solution containing both butane and beneficial cannabis compounds is then placed in a vacuum oven in order to evaporate, or purge, the BHO of its butane and any other foreign contaminants. There is almost always trace amounts of butane in the oil produced by these extractions, so try to minimize your risk by purchasing lab-tested BHO. Some legal states have begun to place maximums on the amount (PPM) of residual solvent allowed in BHO sold in dispensaries. Make sure your oil is properly purged!
Concentrate derived from a propane-based extraction is referred to as Propane Hash Oil, or PHO for short. Although others are possible, the consistency of PHO is typically budder. The process of propane extraction is very similar to butane extraction, the primary difference is simply swapping butane for propane. Propane extractions run at higher pressures, stripping different ratios of plant waxes and oils than butane which, depending on the strain, can deliver fewer residuals and higher levels of terpene preservation. Propane has a lower boiling point than butane, which allows for a lower purging temperature for PHO and results in the buttery consistency as opposed to shatter. Note that some extraction companies utilize a blend of propane and butane.
CO2 oil is the golden liquid used in almost every pre-filled vaporizer pen cartridge. CO2 oil is substantially safer than propane and butane-derived extracts. CO2 oil is a clean, dab-able product once removed from the extraction machine with no harmful residuals or risk of toxicity. Another upside to CO2 extractions is that it kills any mold or bacteria present in the plant material. Although safer to consume, in my experience, CO2 oil lacks the flavor profile (terpene content) present in BHO and PHO. CO2 oil is commonly used in edibles and can be purchased in its activated form.
CO2 extractions almost always produce a viscous oil (color can range from amber to dark) that is typically delivered in an oral syringe. However, secondary refining processes can bring CO2 extractions to a stable, shatter-like state.
Supercritical or subcritical carbon dioxide extractions involve holding the CO2 at high or low pressures, respectively; the process involves extremely expensive extraction machines. The CO2 passes through the cannabis material and strips the plant of its oils, waxes and other matter. By adjusting certain parameters, the extractor can save more cannabinoids and terpenes in order to preserve purity or strip more unessential material like chlorophylls to increase yield.
Concentrated extracts can also be created by soaking ground cannabis in alcohol (either isopropyl or Everclear). A short soak is all that is needed to isolate the cannabinoids and terpenes from the starting material. A longer soak will also dissolve undesired plant materials like chlorophylls and waxes. Alcohol-based concentrates are safe to make at home and are safe to consume, assuming the solution has been filtered and purged. Purging, or evaporating, the alcohol requires precise temperature control and patience. This type of concentrate, also known as Rick Simpson Oil, is typically consumed orally or via tincture.
Distillation, also known as isolation, is a form of extraction and refinement that separates full spectrum plant oil into its individual constituents – meaning you can isolate the THC, CBD, and terpenes individually from a batch of full spectrum oil. This allows the extractor to achieve extremely potent concentrates that only contain one of the many compounds found in the cannabis plant. Although it is generally accepted that full spectrum extracts provide higher medical efficacy, isolate is useful because it gives people access to specific cannabinoids (like CBD) in higher quantities than can be found in flower. For instance, CBD isolate typically contains 99% CBD, indicating a very pure product. Another benefit to CBD isolate is that it can be shipped all over the U.S. because it doesn’t contain any THC.