Medicinal After their triumphs in the US and Canada, cannabis extracts are also gaining popularity in Europe. While consumers really value the relaxing effect of so-called “infused edibles”, extracts that are easy to dose and simple to standardise are particularly useful for medicinal applications. Cannabinoid extraction is a science in its own right, and goes much further than what the average consumer is concerned about. The “710” culture (if you turn 710 upside down, it looks like OIL!) is finding more and more fans wherever growing cannabis is either tolerated or legal.
After their triumphs in the US and Canada, cannabis extracts are also gaining popularity in Europe. While consumers really value the relaxing effect of so-called “infused edibles”, extracts that are easy to dose and simple to standardise are particularly useful for medicinal applications. Cannabinoid extraction is a science in its own right, and goes much further than what the average consumer is concerned about. The “710” culture (if you turn 710 upside down, it looks like OIL!) is finding more and more fans wherever growing cannabis is either tolerated or legal. 710! is maybe the Champagne of consuming cannabis for a high. It is much more about texture, aroma, consistency and combination of active ingredients than about the ultimate high – even though that is definitely still part of the package.
But a new culture can only develop where the production of the necessary ingredients is no longer criminalised, at least for personal consumption. That is why Spain, with its Cannabis Social Clubs, has become the dabbing capital of Europe, while even in the Netherlands, because of the classification of cannabis oils as hard drugs, it is difficult or impossible to find good extracts.
With or without solvent?
The most commonly used solvents to extract oil from cannabis flowers or the remains of the harvest (trim) are ethanol, isopropyl alcohol, propane, dimethyl ether, CO2 and butane. The final product, depending what you started with, and the length and method of extraction, will contain almost exclusively the constituents that are to be extracted from the plant. As a result, THC or CBD contents between 70 and 98.5% are quite normal for cannabis extracts.
Not all solvents are equally harmless and isopropyl alcohol (commonly known as “rubbing alcohol”) is basically to be avoided for health reasons. Butane (BHO) extraction brings other problems to the table, as this solvent is highly explosive and therefore regularly the cause of severe accidents in the illegal cannabis refineries of the world. In Colorado, the production of extracts became a political football after legalisation, because there were a growing number of people who were severely injured or killed. In 2014, there were 32 accidents with a total of 17 people injured in the production of cannabis oil where BHO was used. This led legislators to legally regulate cannabis extraction in 2015. Until then, given the legal status of cannabis, there was no way to bring the people causing the explosions to justice. Since then, only licensed cannabis producers are allowed to make extracts using butane gas. The use of a naked flame in the extraction process is also totally forbidden now. In addition, municipalities in Colorado have the option to designate special zones for the production of cannabis extracts. Denver has already done so and extraction is only allowed in industrial districts there. Infringements are punished with jail sentences of up to 16 years. Private individuals who want to produce their own grass or hashish oil may only make use of classic methods, such as those using alcohol or heat extraction.
The least troublesome and absolutely residue-free form of extraction uses CO2, but a very special and expensive installation is needed. A relatively small 10-litre extraction system costs around EUR 40,000 at present on the US market. Under high pressure (at least 73.75 bar), the compressed, so-called supercritical CO2 dissolves the desired substances in the plant material. When the pressure is reduced, the CO2 releases the extracts again. Process parameters such as temperature, pressure and time are tuned to suit the raw material. The terpenes and cannabinoids are preserved and can develop their full effect when used in the form of a full extract. Simple physical processes replace the chemical reactions: Supercritical CO2 is an inactive substance and does not react with the substances being released. The supercritical extraction enables the concentration of valuable ingredients in their unchanged, natural form. Using moderate temperatures and the addition of oxygen, the process is especially suitable for extracting sensitive oils and extracts.
In US states where cannabis is legal, some producers have recently started using the so-called “live resin” extraction method. Here, freshly harvested plants are flash-frozen. As soon as the plant material is rigid, the substances it contains are extracted using one of the methods described above. In this way, the terpenes, cannabinoids and resinoids that otherwise are lost during the drying process all remain in the full extract. Connoisseurs describe the difference in taste as being roughly like that between pasteurised and freshly pressed juice.
Cleaning and refining
There are a variety of techniques available to clean your extract from all traces of solvent. The simplest and best is just to wait. After a few months, all the volatile components will have evaporated, but in this time, the concentrate can become contaminated with dust particles. When using high temperatures to dry the extract in a process known as “heat-purging”, too many terpenes evaporate. Normally, manufacturers use a vacuum chamber to purify their extracts. This involves reducing the pressure in the chamber so that the solvents boil at a lower temperature and evaporate faster. Also, if the chamber is slightly heated as the vacuum is created, the drying time is significantly reduced. The fairly young 710 scene is still arguing about the optimum temperature. Ed Rosenthal recommends a temperature of 34°C-37°C, German online forums talk about approx. 50°C. Some cannasseurs also filter the lipids and waxes extracted from the plants, which is known as “winterizing” and “dewaxing”. But removing the plant’s own lipids and waxes is very controversial, because the centrifuging or filtering process also removes terpenes and other components that dissolve in fats.
As well as the various methods of producing concentrates using solvents, there are also solvent-free techniques to create “non-solvent” extracts, such as the classic dry sifting, ice water extraction or the relatively new “rosin tech”.
The dry extracts can compete with the “solvent extracts” in terms of active substance and terpene content. In Spanish Clubs, you regularly find extremely carefully sifted, unpressed hash with up to 90% THC content. The strongest of the sifted extracts are therefore almost as strong as the highly potent solvent extracts. Only with the rosin-tech, which works with a simple iron and a sheet of greaseproof paper, are the desirable terpenes lost because of the higher temperature. The THC concentration of the over 70% on average is easy to demonstrate, even with the simplest of all the extraction methods.
Shatter, Wax, Honeycomb, Sap, Budder, Live resin or what?
The colour and consistency of extracts are not necessarily the right criteria for quality. On the one hand, the consistency and texture depend on the combination of the different cannabinoids, terpenes and lipids, together with parameters such as ambient humidity, temperature, solvent and many other things. If everything is perfectly mixed and dissolved, the final product is as clear as glass. But even if the result can be influenced by various parameters such as the solvent used, the variety, temperature and pressure or extraction duration, the final consistency is always a surprise in 710! circles. This is of course not the case for medicinal extracts, which are produced to a standard under constant laboratory conditions and from the same initial materials.
Shatter: The English word “shatter” perfectly describes the hard, shiny, transparent consistency. The extract easily breaks up into pieces and has a glassy consistency at low room temperatures. Shatter is translucent, because its molecular structure is retained during production.
Sap: Sap describes a transparent, soft, viscous, sticky consistency of cannabis concentrates. Its consistency is generally a little sticky, flexible, oily and relatively easy to process.
Wax/Budder: These are the names for opaque extracts that have lost their transparency after extraction. If you stir these opaque extracts vigorously then they take on a fluffy, matte consistency that is called wax or budder in expert circles.
Honeycomb: Looks like Swiss cheese. This is a cleansed extract. The bubbles that are created by the evaporation of the solvent under vacuum create the unusual texture of this extract. Exists as wax and shatter.
Crumble: Live resin extracts in particular often have a consistency like cane sugar, because the original material contains a relatively high level of moisture. Extracts with a sugary, crumb-like consistency are called “crumble”. This granular consistency often only occurs after storage, because the extract has absorbed humidity from the air during storage. This process is known as “sugaring”.
Dabbing rig – an “objet d’art”
If it is done properly, the cannabis concentrate should be very reminiscent of the strain from which it was produced. The odour, taste and effect of a variety are intensified by the process, because all the active ingredients are present but intensified. A typical dab set-up to vaporise extracts consists of a small glass bong, BHO pipe or bubbler, with a glass or titanium needle (or other heat resistant material) and a glass dome. Concentrates are best stored in a non-stick silicon container or simple greaseproof paper.
In the US, the 710 movement has spawned a glassblower culture, which is much further advanced than the rest of the world. The colourful dabbing rigs are carefully produced works of art, with prices which can easily run to several thousand euros. In the US and Canada, art lovers have discovered these glass ornaments as investment items, as they can be collected in the same way that paintings or sculptures are. In the meantime, insiders reckon that about 1,000 glassblowers in the US and Canada make a living from blowing expensive pipes for dabbing enthusiasts.
How sensible is an upper limit for THC in extracts?
Newcomers or inexperienced consumers who have negative consumer experiences from “edibles” that are too strong, are still considered to be news by many media. A substance in a concentrated form is of course stronger and therefore needs to be dosed more precisely (i.e. by milligram) than in its natural form (i.e. by gram). However, because of the lack of labels and warnings on the European black market, this is not possible. If the manufacture of these products becomes legal and the active ingredient level can be determined to the milligram, as is done in the US and Canada, and clearly declared, then the potential threat from extracts is significantly lower than that posed by cannabis buds or hash consumed orally.
But an upper limit for the THC content in extracts, as suggested by some experts, will not be effective. Similar attempts to regulate alcohol have had as their result that while the commercial sector does adhere to a maximum level for alcoholic drinks, it finds other ways around it. Pure alcohol, known in the US as “Everclear” or in Germany as “Prima Sprit” or “Weingeist”, is fairly widespread as a basis for party cocktails that pack a punch. Officially, it is not sold as a drink; rather, it might be marketed as a product for cleaning glass or as the basis for preparing tinctures. Consuming pure alcohol, unlike a 99.5% THC extract, would probably be fatal. It is not banned, because nobody really sets out to drink the stuff undiluted, which is why it can be obtained quite legally, with the relevant warning messages, despite the maximum alcohol content limit for spirits.
Transparency about the contents, along with adequate warnings and dosing instructions and appropriate information on the packaging, would enable cannabis consumers to sensibly handle extremely pure concentrates. Regulating cannabis should not mean that expensively produced, very pure extracts need to be cut in order to achieve a lower level of active substances and remain legal. A ban would also contribute to the mystification of these very pure concentrates and push the price up, without having any great impact on availability or on people with problematic consumption tendencies. We have ample proof of this from 50 years of banning cannabis. Last but not least, a maximum THC level would make access for those patients who really need a high concentration of active ingredients more difficult, and unnecessarily so.