by Ed Rosenthal
In the Hi-Flo process, liquid CO2 is pumped through a pressure vessel filled with dried, ground herb. The CO2 dissolves plant oils and carries them to a separator where the stream is depressurized and heated, causing the CO2 to flash vaporize and drop the oil to the bottom of the separator. The CO2 drops into an accumulator and flows back to the pump and extractor vessel in a continuous loop. At the end of the cycle, the CO2 is pumped back to a storage vessel so the separator can be opened to collect the extract.
The Commercial Vacuum Distiller offers five methods of extraction and four methods of distillation, and has multiple upgrades allowing for use with a variety of gases and solvents, as well as the ability to act as a fractionating separator. It can be fully automated.
Alcohol- and glycerin-based tinctures.
Photo: Steep Hill Halent
Chapter 9.
Tinctures—
Alcohol and Glycerin
Before cannabis prohibition tinctures were the most common way of buying and consuming marijuana in America. Recently, they’ve been making a comeback. Commercially prepared tinctures are now available in dispensaries in many states. Tinctures are discreet to use and are quite easy to make at home.
A tincture is a concentrated extract of any herb in liquid—usually alcohol, sometimes glycerin—that is taken by mouth as a drop on or under the tongue. Alcohol is used to separate the cannabinoids, terpenes, and other essential oils from the marijuana plant material and acts as a preservative. In herbal medicine, tinctures are commonly 25% alcohol, which is achieved by diluting the mixture with water. People who do not want to consume alcohol may opt for glycerin-based tinctures.
Methods of making alcohol tinctures of marijuana vary from extremely simple and low tech to complex distillation apparatuses that produce highly purified cannabis oil. The easiest way to make tinctures is an alcohol soak. All that’s required is a bottle of 100 proof or higher drinking alcohol and cannabis leaf, trim, bud, or kief. Add the cannabis to the liquor, let it soak for at least a week, then strain (or not) and enjoy.
CHOOSING THE ALCOHOL
No matter what type of marijuana is going into the tincture, starting with a quality solvent is important. The purist grade alcohol is USP medical-grade 190- or 200-proof neutral grain spirits. It is available from laboratory supply companies.
More commonly available is 190-proof Everclear brand alcohol, which can be found at liquor stores in 40 of the 50 states. Note that Everclear is marketed in two strengths: 150 proof (75% alcohol) and 190 proof (95% alcohol). Get the 190. Sale of Everclear 190 is banned in California, Florida, Hawaii, Iowa, Maine, Minnesota, New York, Nevada, Ohio, and Washington.
An alternative high-proof option that is available in some of those states and online is an extremely pure form of Polish vodka called Spirytus that comes in at 192 proof, or a percent purer than Everclear. Polmos Spirytus, Spirytus Rektyfikowany, and Baks Spirytus are some of the brands that can be found in the United States.
If these purified options are unavailable or you are interested in a little flavor, other high-proof liquors can be used, such as Bacardi 151-proof rum. There are a number of brands of 100–120-proof vodkas and rums that can be used.
TYPES OF ALCOHOL
Know the difference between ethanol alcohol versus denatured and isopropyl alcohol. Ethanol-based tinctures and extracts can be ingested or used topically. Extracts made with isopropyl alcohol are poisonous and cannot be ingested safely. They can only be used externally.
Ethanol is sometimes called ethyl alcohol. If buying medical- or laboratory-grade ethanol, double check to be sure that it has not been denatured. Denatured ethanol is the kind put in vehicles.
Denatured ethanol and isopropyl are poisonous taken internally and can kill you. They can be used to make topical products for external use only. They should never be consumed or ingested.
THE HERB
Tinctures made with different varieties of marijuana have varying effects because of the entourage effects that the terpenes, the odor molecules, create. Plant parts being used, maturity at harvest, and post-harvest processing all play a part in determining the tincture’s potency. Leaf, trim, bud, kief, and hash are some of the choices, and all are used.
Commercially available Full Extract Cannabis Oil is refined using only food-grade ethyl alcohol and can be used topically and internally.
Photo: Nadim Sabella Photography
When used for medicinal purposes, a tincture with CBD as well as THC may be beneficial. Some medical tincture makers have adopted cold-processing methods to avoid decarboxylating the cannabinoid acids. Not converting THCA to THC increases possible dosage levels because the THCA does not activate the high, but its medical qualities remain.
If marijuana has been dried and cured as it would be for smoking, some decarboxylation will have already taken place, so THC and CBD will be present without using heat, just not as much. Raw fresh or dried marijuana leaves can be used to make tinctures, though the resulting product may have a chlorophyll flavor. Gently soaking the dried marijuana in water removes some of the chlorophyll, which dissolves in water. Adding a bit of honey to the finished tincture can make it more palatable.
If using fresh plant material, fill a glass container with herb, then add alcohol (ethanol) to the top. If using powdered, dried herb, figure roughly one ounce of weed for every four ounces of alcohol. Use a butter knife to stir the mixture to release air bubbles trapped in the plant material. Cover it. Let it steep in a cool, dark space for two weeks or more. Shake the container daily to mix the ingredients and help the alcohol dissolve the terpenes and cannabinoids. Then strain out the plant material using a sieve lined with cheesecloth set on a glass or metal bowl. The length of time it steeps results in slightly different tinctures. A longer soak extracts more cannabinoids and essential oils, making it stronger and more concentrated, but it also leaches out more of the plant’s other chemicals, such as chlorophyll. Splitting a batch between several jars that can be left to steep for differing amounts of time can help you determine what works best for you.
If you’re using dried marijuana and want a tincture with the most punch possible, carefully heat the marijuana first. Just spread the leaves, trim, or bud on a cookie sheet and put it in the oven at 125°F (52°C) for an hour. This decarboxylates the THCA and other cannabinoid acids to a more potent form. Heating at a higher temperature would cause most of the terpenes, the odor molecules, to evaporate. Higher temperatures also convert THC to the less potent, more sedative CBN. There is no need to grind the marijuana before adding it to alcohol because the cannabinoids and terpenes are almost all on the surface. Grinding results in more sludge collecting at the bottom.
THE HISTORY OF HEMP TINCTURES
Tinctures were the delivery method Western medicine used for marijuana for more than 90 years. Major U.S. pharmaceutical companies produced them from the mid-nineteenth century until cannabis was removed from the United States Pharmacopeia in 1942. The Marihuana Tax Act of 1937 made production of cannabis medicines prohibitively expensive, and there was a turn away from botanical medicines to synthesized and purified drugs than could be injected. THC had not been discovered, and no one knew what was creating marijuana’s effects or how to standardize them. This created significant quality control issues.
Our ability to test for the cannabinoids provides the opportunity to produce dose-controlled medicines. GW Pharmaceuticals in the U.K. has registered Sativex, a 50:50 THC:CBD extract, and Epidiolex, a high-CBD extract. Both drugs are alcohol-based marijuana tinctures that are sprayed under the tongue. Dispensaries in some states sell many versions of tinctures, so patients have many choices.
When the same material is used repeatedly to extract cold-water hash, each pull will have a lower quality, with more vegetative material and a strong botanical smell, but it is excellent for making tinctures. Be sure to filter the collected material using screens, high-grade cheesecloth, or a coffee filter.
STRAINING
To
strain the tincture, line a sieve or metal colander with cheesecloth and place it over a clean metal or glass bowl. Pick the type of cheesecloth based on how big the plant particles are that you want to catch. Cheesecloth comes in different grades, based on how tight the weave is, just as printing screens that can be used for sifting kief are graded based on how fine the mesh is. Cheesecloth grades range from the very loosely woven #10 to the extra-fine #90. Unlike the symmetrical mesh of metal and plastic sifting screens, the number of threads per inch in cheesecloth varies horizontally and vertically, as seen below.
Use a looser grade for straining freshly chopped plant material; it catches the plant material and does not clog. Cheesecloth grade #60 to grade #90 is best for straining ground and powdered dried herb for tincture making to avoid sludge build-up. Using fine-grade cloth requires patience because it takes a long time for the extract to seep through. Once gravity has done all it can to pull the tincture through, lift the cheesecloth carefully up by the corners from the sieve and squeeze any remaining solution into the bowl.
If kief or powdered, dry herb is used to make tincture, even the finest cheesecloth or pastry cloth will let some sludge particles through. A second pass through a paper coffee filter or a #1 laboratory filter yields a cleaner, particulate-free product.
Another way to separate the dissolved THC and terpenes from the brew is to use a colander lined with cheesecloth to remove most of the particles. Squeeze the solution from the cloth. Place the cloth back in a bowl and add virgin alcohol. Dip the bag as if it were a teabag to capture more cannabinoids in the alcohol. Warming it gently on a well-ventilated electric stove to about 100°F (38°C) makes the cannabinoids more soluble. Careful: Alcohol fumes are explosive so this should be done in a well-ventilated space or outdoors. Add the new cannabinoid solution to the first one.
Place the solution in a wide-mouth glass jar or pitcher and cover it. Then let it sit in a cool dark place undisturbed for several days or more. Vegetative material mixed into the liquid will separate, either floating to the top or sinking to the bottom. The alcohol solution is fairly pure. Gently skim the floating material from the top. Then siphon the solution from the top, leaving the sunken particulates undisturbed. The siphoned solution can easily be purified further using fine filters, which it passes through very quickly.
ASK ED’S FAST-TRACK TINCTURE
Traditional tincture recipes talk about an aging process: “Let the mixture sit for…” The reason that the tincture gets stronger as it ages is that, at least in theory, more of the THC and other cannabinoids dissolve in the alcohol as time passes. This method speeds up the process by giving the dissolving cannabinoids a quick mechanical assist.
Equipment
•Disposable neoprene or latex gloves
•Blender
•Metal slotted serving spoon
•Colander
•Fine mesh strainer
•Glass or stainless steel bowl, sized to hold colander
•Cloth kitchen towel
•Amber or cobalt blue glass jar with sealing lid
•Funnel (optional)
Ingredients
•Bud, trim, or leaf material
•Grain neutral spirits such as Everclear or overproof alcohol such as 151 rum or vodka
Method
Weigh the marijuana. For every ounce of herb use ten fluid ounces of alcohol. A 750 ml bottle of alcohol is 25.4 fluid ounces, so a full bottle is good for just over two and a half ounces of weed.
Place the marijuana in a colander up to one-third full. Do not break up the leaves or buds so that the glands remain on the leaf surfaces. Place the marijuana-filled colander in a mixing bowl. Add enough cool—not cold—water so that the marijuana can spread out. Let the weed sit in the water bath for an hour or so to dissolve the nonactive, water-soluble pigments and carbohydrates from the plant material.
Pull the colander from the water and let the water strain out of the plant material. Wearing gloves, roll the marijuana into a ball. Wrap it in a clean dish towel and squeeze out as much water as possible.
Place the strained plant material in a blender. Add ten ounces of alcohol for each ounce of marijuana. Place the cover on the blender. Blend at the lowest setting for five minutes. Let it sit for an hour, and then blend on low again for five minutes. Pour the blend into a bowl or wide mouth pitcher. Let the mixture sit for a couple of hours so that the leaf floats to the top of the alcohol.
Using a slotted spoon, remove the large floating debris and put it in the fine mesh strainer with the mixing bowl underneath to catch the drainage. Using gloves, press the herb against the strainer to squeeze out the liquid into the bowl. Break up the ball and let it soak in a small amount of virgin alcohol to dissolve remaining cannabinoids. Then repeat the squeezing process, and discard the plant material. It can also be used as a poultice.
Pour the liquid through the fine mesh strainer over the bowl. Depending on how fine the mesh and how good the blender, you may see tiny insoluble plant particles in the bowl. If so, filter the tincture through a coffee filter or ultra-fine cheesecloth. If you are using a funnel for transferring the tincture to jars for storage, put the coffee filter or fine cheesecloth inside the funnel and filter while you fill. The tincture is ready to use but a little raw.
Test the tincture. Ideally a dose will be no less than a dropper full. If it is too strong, add alcohol or water. If it is not strong enough, concentrate it by evaporating some of the alcohol. Placing the marijuana in an open mixing bowl in a warm room speeds alcohol evaporation. Covering the bowl or jar with cheesecloth slows evaporation but keeps out dust and dander. Within a few hours the bowl will contain visibly less liquid. Once the tincture is concentrated to the strength desired, put it in a clean, dark glass container and seal it tightly. Store refrigerated in the dark. Long exposure to warmth and oxygen degrades cannabinoid content.
QUICK WASH METHOD
For the purest extract, a quick alcohol wash can be used. This method leaves more of the chlorophyll and other water-based chemicals behind and reduces the time the extracted oils are exposed to alcohol and any potential chemical changes.
•Start with dried, cured herb. Do not grind.
•Place on a cookie sheet in a 100°F (38°C) oven until bone-dry and brittle.
•Place the herb in a glass jar and put it in a freezer to dry further.
•Add high-proof ethyl alcohol and shake to make sure all the vegetation is thoroughly wet.
•Return jar to freezer for one minute.
•Remove jar from freezer, shake, and return to freezer for another minute.
•Repeat.
•After three minutes, remove jar and strain the mixture through a fine wire mesh that lets it drain quickly.
•Refilter using a coffee filter or a #1 laboratory filter.
•The resulting tincture can be used as is or reduced to oil.
•Reprocess the strained plant material for a second batch with different properties. Because the quick wash technique is so rapid, there will still be a considerable amount of cannabinoids remaining. If using kief or hash instead of trim or bud, you can skip the oven drying step.
BOTTLING AND STORAGE
Once you’ve filtered the tincture, use a funnel to fill the storage bottles. Tincture bottles, sometimes called “Boston rounds,” should be glass and either amber (brown) or cobalt blue. Do not use clear glass—light causes the cannabinoids to degrade. Do not use plastic bottles—the alcohol will leach potentially harmful chemicals from the plastic. Amber glass bottles are widely available in sizes from 0.5 ounces to 32 ounces. The most common sizes for use with droppers are between 0.5 and 4 ounces.
For applying the tincture, you will want at least one or two tops with built-in droppers sized to the depth of the bottle. For storage, use regular, solid screw caps; they seal better.
Label the tinctures by variety, solute, and date. Keep tinctures in a refrigerator, which slows degradation of cannabinoids to a crawl. They can be sto
red for years, without losing much potency.
REDUCING TINCTURES TO OIL
Cannabinoid-rich oil can easily be extracted from alcohol tinctures because alcohol evaporates rapidly, particularly when heat is applied.
A Slow but Safe No-Effort Method
Alcohol evaporates at room temperature, so leaving the top off the tincture bottle or putting the tincture in a bowl or pan for a while reduces it. This works, but it is slower. Remember to cover the jar, bowl, or pan with fine-grade cheesecloth to keep out dust and dander.
The Faster Heat Method
Alcohol boils at 173°F (78°C), below the temperature at which cannabinoids vaporize. That means careful use of controlled heat can be used to boil off alcohol from a tincture, leaving only cannabis oil.
Remember: Alcohol is highly flammable—its fumes are explosive. Use a double boiler over an electric hot plate (no flame) to evaporate the alcohol. Provide ventilation, removing the fumes from the space, or work in an open outdoor space.
Rules for Heating Alcohol
•Avoid open flames.
•Don’t use gas stoves or pilot lights.
•Use only electric stoves that have a protected heating section.
•Absolutely no smoking or vaporizing anywhere in the vicinity.
•Work in an extremely well-ventilated area—preferably with a lab ventilator.
•Keep windows open and ventilated using box fans turned to blow air out of the room.
•Wear cotton clothing. Do not wear wool or silk, which produce sparks of static electricity.
Temperature control is critical when reducing tinctures. Never heat a tincture by placing it directly on a burner or stove top, as there will be large differences between the temperature at the bottom and the top. The overheated bottom will produce chemical changes in the extracted oil that will rob it of potent cannabinoids.