The extraction of phytochemicals from cannabis is a crucial step in order to collect bioactive molecules from the plant matrix and produce innovative products to benefit from the potential therapeutic effects.
Among other solvents, butane can be used to isolate cannabis constituents. The list includes:
- And cannabinoids.
High amount of the psychotropic cannabinoid tetrahydrocannabinol (THC) can be extracted if the process is performed using high THC-containing cannabis plants.
Butane hash oil (BHO) is the concentrated viscous resin produced extracting cannabis inflorescences with butane : the concentration of THC can be up to 90% and the consistency and appearance can change depending on the extraction and post- extraction procedures.
Different Kinds of Butane Hash Oil Extracts
It is possible to make different kind of BHO extracts by altering the conditions.
- Live resin — if the process is performed on freshly harvested and frozen cannabis buds;
- Terp sauce — if the butane is left with the plant material for a few weeks at low temperatures in order to collect more aromas and flavors;
- The shatter — if the butane extract is collected in a thin layer and then the solvent gently evaporated.
The list above is far from being complete — the BHO extracts world can provide multiple other extremely powerful and popular options.
BHO diamonds are obtained starting from the live resin extract and performing a crystallization process capable of separating terpenes and flavonoids from the desired cannabinoid to be isolated: the result are literally diamonds of incredible strength and purity difficult to be reached otherwise.
Another kind of product that can be made through butane extraction is wax, that is a sticky ultra-potent resin with THC levels nearing 50-90%: to obtain this extract the concentrate is gently agitated during the purging process creating the particular texture.
Similarly to wax, if the concentrate is greatly agitated during the purging process the final product is called budder. The consistency resembles cake frosting — it’s neither liquid, nor it is solid.
If the purging of the solvent residue from the concentrate is performed slowly, at low temperatures in a vacuum oven, the obtained BHO product is called crumble. Sometimes called “honeycomb”, it has its name for a reason: it’s a dry substance that’s truly easy to crumble in your hands.
FInally — BHO, Butane Hash Oil
The more liquid form of BHO extract is the oil, which can be difficult to handle and it is generally used to produce other cannabis derived products, such as moon rocks. Sometimes it’s added to cannabis inflorescences in order to enhance their potency.
BHO extraction process
The extraction process is performed dissolving cannabis constituents into the butane that is then let evaporating. The concentrate resin left behind is the BHO and can be processed into the aforementioned products through different methods.
A strong point of the BHO extraction process compared to other methods is the fast run time (just under 30 minutes) and the fact that butane is easily evaporated. Another benefit is — it’s capable of reducing the extraction of undesired compounds such as chlorophyll and waxes. The low temperatures permit the selective extraction of compounds and make it possible to preserve sensitive plant constituents.
Closed-Loop or Open-Loop System — How BHO is Made
BHO can be made using various extraction systems like the open-loop extractor or the closed-loop extractor. Both are capable of isolating cannabis constituents efficiently, keeping high amounts of terpenes thanks to the applied low temperatures (-40 °C) to keep the butane liquid during the extraction process.
A closed-loop system is superior to an open-loop system in multiple ways. Even though there’s no way to say that it’s 100% better, in case you need to choose just one — keep in mind that a closed-loop system gives you an ability to:
- Re-use the extraction solvent several times;
- Avoiding waste;
- Reduce the risk of solvent evaporation in the outside environment;
The final benefit is, an average closed-loop system allows you to reduce the possible contamination of the extract during the process.
How to make BHO Extracts Productions Safe? The Safety Rules
One of the major concerns about butane extraction is the fact that at room temperature the solvent is a gas, particularly flammable even at low percentages.
The gas accumulates close to the floor and even a small spark could cause a disaster.
To avoid the risk of explosion, various precautions are necessary:
- The extraction process should be performed by experienced technicians;
- The machinery has to be checked and cleaned properly;
- Alarm systems are a MUST in the laboratory (or at least in the extraction room) in order to detect risky solvent levels in the air.
Even if butane is easily evaporated at room temperature or applying a minimum of heat, it can happen that low amounts of solvents stay in the final product and this could then contain toxic quantities of residual hydrocarbons of the solvent.
Moreover if the butane used is not pure enough, the final extract could contain harmful quantities of contaminants such as xylene and toluene.
For this reason, even though BHO extraction is a relatively straightforward method, it is better to always consume extracts made by reliable producers and provided with the certificate of analysis (COA).
BHO and policy arguments
There is a lack of scientific literature about the use of BHO and only few studies reporting the use of this kind of cannabis extracts and the potential health risks associated. Often users are not aware of the actual potency of these concentrates and the production of BHO can be particularly dangerous if the process is not performed by trained operators in well-equipped and controlled facilities.
More studies should be done on the use of BHO and the benefits associated to its use in medical settings, the potential risks associated with BHO consumption and the risks associated with amatorial produced BHO concentrates.
The intense production of cannabis concentrates and the deregulation of BHO products may lead to increased use of these cannabis derivatives. Young generations may become the major recreational consumers of BHO extracts, driven by the idea that vaporized cannabis concentrates can be healthier than smoking cannabis inflorescences.
In addition of high THC concentrated Butane hash oil extracts, it is possible to obtain high concentration of the non-psychotropic phytocannabinoid cannabidiol (CBD) in the final BHO that can be used in medical environment to deliver high quantities of this potentially beneficial compound for certain health issues.
More research about BHO products and cannabis administration alternatives could ameliorate the policy arguments about this topic, helping in the development of laws to regulate recreational and medical BHO consumption, together with amatorial and professional BHO concentrate production.