At first glance, cannabis concentrates can seem intimidating to the average consumer. There’s a lot of science involved, and there are plenty of types of concentrate to choose from - so much so that sometimes you may not know what makes any two extracts different from one another, or what a concentrate even is. Put simply, concentrates are the extracted cannabinoids and terpenes from the cannabis plant. The different types of extracts that can be consumed vary depending on what method of extraction is used. All extracts can be divided into two categories: solvent-based and solventless.
Difference Between Solvent-Based Concentrates and Solventless Concentrates
If solvents are the more chemical method of extraction, then solventless methods could be considered more mechanical. Where chemicals are used to separate the essential oils from the plant matter, techniques involving filtration, heat, and pressure are used for solventless concentrates like hash and rosin. Solventless concentrates generally require more work and have smaller yields, which is why they tend to cost more. However, they are considered to be “artisanal craft concentrates” and are highly sought after by connoisseurs. Because solventless extracts are all-natural, there’s also no risk of consuming any residual chemicals that may be present in poorly purged solvent-based extracts.
How Solvent-Based Extracts Are Made
Hydrocarbon Extracts
When it comes to different types of solvent-based concentrates, there are a lot of factors that determine what type of extraction you’re going to yield, but the biggest one is the solvent used. The most popular concentrates are probably hydrocarbon extracts, which are sometimes referred to as butane hash oils (BHO.) This, however, is incorrect. Any extract that is produced using a hydrocarbon solvent is a hydrocarbon extract, but not all hydrocarbon extracts are made using butane (although it is probably the most commonly used.) That being said, another hydrocarbon that is rising in popularity as a solvent is propane, resulting in propane hash oil (PHO.)
Regardless of which hydrocarbon is used as a solvent, the extraction process is fairly similar. The liquid solvent is washed over the cannabis material in a closed loop to separate the cannabinoids and terpenes from the plant material. The solution is then filtered for impurities.
Next, the concentrate has to go through a process called purging, during which the solution is heated so that any residual chemicals evaporate from the extraction. The end result is a solvent-free (not to be confused with solventless) concentrate, ready to be consumed. The consistency of the hydrocarbon extract depends greatly on how the concentrate is handled during the purging process. If the concentrate is whipped while still moist with terpenes, you'll end up with what's often called badder, budder, frosting, or icing. Conversely, when the waxes are purged from the extract, resulting a drier texture, you get what's called honeycomb or crumble, named for its porous, crumbly consistency. If the extract is poured out onto a flat sheet and left completely undisturbed during the purging process, you get a brittle, almost glass like consistency, called shatter.
CO2 Extracts
As the name suggests, CO2 extracts are made by using carbon dioxide, temperature, and pressure to extract the cannabinoids. Unlike BHOs or PHOs, the CO2 extraction process is generally considered to be safe - carbon dioxide is already present in the air that we breathe and it’s a non-combustible gas. Another thing that makes CO2 particularly different from other solvent-based extracts is when carbon dioxide is used as a solvent, it’s used in its super-critical state, which gives it the properties of both a liquid and a gas. CO2 extracts have a little more of a viscous consistency, and are often used in vape cartridges and applicators. They can also be further refined to make distillate.
Distillate
In the above mentioned methods of extraction, while the cannabinoids are more concentrated than they are in flower form, they still contain other plant compounds such as terpenes, fats, and lipids. All of these compounds affect your high in the same way they do in flower - after all, the difference in terps is one of the main things that separate strains and their associated highs from each other. However, if you’re just looking for the highest THC possible in your cannabis, then distillates are the way to go. Because this is the most refined form of THC, most of the plant matter has been removed, resulting in THC percentages that can hit upwards of 90%. Distillate is also virtually flavorless and odorless, so it’s a popular method of infusing edibles. Distillates are also a popular extraction for cartridges and applicators, and some companies will even re-add natural terpenes to their distillate cartridges to reintroduce some of that flavor back into the extraction.
How Solventless Extracts Are Made
Types of Solventless Extracts
There are a plethora of categories of solventless cannabis concentrates, but the main three we’ll be talking about are dry sift, bubble hash, and rosin.
Dry Sift
If you have a kief catch on your grinder, then you’ve essentially collected a less refined form of dry sift before, as the method of extraction is extremely similar. Dry sift is simply the collection of resin glands (where the THC is stored) that have been separated from the flower using different sized mesh screens. In order to separate the resin glands from the plant, extractors will tumble, rub, and roll dried cannabis over a very fine screen. This extremely physical process causes the trichomes to break off and fall through the screen, while everything larger than a trichome stays on top. To further refine the dry sift, some processors will use static electricity to separate the resin.
Much like how most people use their kief, the more refined dry sift is often used as a bowl topper or added to joints for a more intense high. Other consumers will sometimes press it into traditional hash, or will turn it into a rosin that you can dab.
Bubble Hash
Bubble hash (also referred to as Ice Water Hash) shares a lot of core principles with dry sift. You agitate the cannabis flower, and then separate the trichomes from the plant through a fine mesh screen. The main difference is that ice water is used in the agitation process. This method of agitation is referred to as washing because hashmakers use washing machines designed specifically for this process. Once the trichomes have been collected, filtered, and dried, what’s left is the bubble hash, although what form of bubble hash you get can vary in consistency, from oily and waxy to dry and powdery.
There are different qualities of ice hash, which are broken down into a star rating system, with 6-Star Hash being the highest quality and 1-Star Hash being the lowest. The highest quality of often referred to as full-melt or ice-wax, and can be dabbed as is, while lower quality ice hash is often pressed into rosin, used as a bowl-topper, or used to infuse joints.
Rosin
Rosin is a dabbable concentrate that is made using nothing but heat and pressure. On an industrial scale, large rosin presses are often used, but you can make your own rosin at home fairly safely and easily with nothing more than some weed, a hair straightener, and some wax paper. You can even buy a small rosin press that’s about the size of a coffee machine for fairly cheap. DIY enthusiasts gravitate towards making rosin because of the lack of chemicals and purging needed for a smokeable final product. The three main types of rosin are flower rosin, hash rosin, and dry sift rosin, with the main difference between the three being the starting product that was pressed.
