How to Decarboxylate Cannabis

Raw cannabis contains a lot of THCA which is not psychoactive. When you smoke weed, the THCA molecule loses its carboxylic group (COOH) in the form of water vapor and carbon dioxide and becomes THC. In short, THCA becomes THC and your cannabis becomes psychoactive. This process is called decarboxylation.

When you smoke or vaporize marijuana, you decarboxylate the cannabis by heating it. If you ingest cannabis and want the full psychoactive effect, you need to first decarb your cannabis before you cook with it.

 

Temperature

The lower the temperature, the longer it’s going to take to decarb your cannabis. Keep in mind that a lower temperature will allow you to lose less terpenes.

 

What are Terpenes?

Terpenes are the pungent oils that color your cannabis with distinctive flavors such as berry, mint, citrus and pine. There are many medicinal benefits to terpenes; some will successfully relieve your stress while others will promote focus and awareness.

 


Table – Decarboxylation Temperatures and Times
TemperatureHeating ModePlant Material TimeKief / Hash TimeCannabis Oil
310FOven10 – 18 minutes5 – 10 minutes
250FHot oil bathUntil bubbles taper off
240FOven50 – 60 minutes30 – 40 minutes
212FBoiling water bath90 minutes90 minutes

 


Decarboxylation Methods:

Tip: Grind your cannabis first! A course grind will allow your weed to evenly dry without losing potency from over grinding.

Flower

  1. Preheat your oven (see table above). Use an oven thermometer to check the temperature.
  2. Sprinkle your cannabis in a pie plate and then cover it well with silver foil by crimping the foil along the edge of the plate.
  3. Place in the oven (see table above) – less time for older drier material, more for fresher material.
  4. After required time, turn the oven off, and remove cannabis. Let it cool down slowly before you unseal the container to allow any cannabinoid/terpenes vapor to reabsorb into the cannabis.

Keif/Hash

  1. Preheat oven (see table)
  2. Sprinkle hash/keif on pie plate, cover with silver foil and crimp foil along edge of plate. Place sealed dish in oven for (see table).
  3. Remove plate and let it cool down slowly without removing cover to allow any vapors to reabsorb into cannabis.

Boiling Bag method:

  1. Place the cannabis flower/keif/hash into a boilable cooking pouch. Seal it.
  2. Place in boiling water for 90 minutes. Make sure water does not boil dry.
  3. Take bag out of water. Let it slowly cool before opening.

Cannabis Oil

  1. Place heat proof container of cannabis oil into a cooking oil bath (canola oil works well). Heat cooking oil to 121C/250F.
  2. Stir cannabis oil to break up bubbles.
  3. Remove cannabis oil from heat when bubble formation starts to slow down — or leave on heat until all bubbles stop for increased sedative effect.
Kief

What is Kief?

Ever wonder what to call all those tiny, sticky crystals that cover cannabis flower?

Well, we’ve got an answer for you: kief.

Simply said, kief (also known as dry sift or pollen) refers to the resin glands which contain the terpenes and cannabinoids that make cannabis so unique. While marijuana sans kief still contains cannabinoids, the resin glands that develop on flower buds pack the biggest punch.

Trichomes: It’s All About Protection

While kief specifically refers to the bulbous, crystal formation on the tip of a gland, the substance itself is just one part of what is called a trichome, or a “hair.”

Many different plants and algae have external trichomes for specific evolutionary purposes. For example, some carnivorous plants rely on sticky trichomes to trap their prey. Other plants, like cannabis, use them as a deterrent to herbivores.

Trichomes on the marijuana plant keep away hungry herbivores by producing an intense psychoactive experience, theoretically disorienting the animal and preventing it from eating the rest of the plant. The resin’s strong, distinct odor also attracts pollinating insects and predators, which might keep herbivore populations at bay.

Extracting Kief

If you like the experience of concentrates but don’t want to break the bank buying expensive wax or extraction equipment, sifting kief might be a great alternative. Due to the high concentration of terpenes and cannabinoids in resin glands, separating kief crystals from plant matter is a great way to consume cannabis while reducing the amount of charred material you take into your body.

Extracting kief is simple. Using a three-chamber herb grinder will help you finely grind your cannabis while letting kief crystals fall through a screen and collect into a small compartment. While two chamber grinders are nice, they often let potent kief go to waste since crystals fall off of the dried herb and just stick to the inside of the grinder.

For extracting larger quantities of kief, using simple silk screening materials will allow you to separate kief from plant matter with the ease of sifting flower.

Many people create makeshift sifters using layered screens similar to the ones pictured above. Because kief tends to measure between 75 and 125 microns, it can be difficult to separate all of the resin from the plant materials. To make sure you’re collecting the cleanest kief without unwanted plant matter, stack three to four layers of fine mesh screen one on top of another.

For the best results, home extractors use consecutive sizes of screen and stack them in order from largest to smallest. When buying screens, the number of wires or threads per inch, or the LPI (lines per inch) number is an important thing to remember. The larger the screen, the smaller the LPI number. When it comes to sifting kief, mesh between 80 and 270 LPI tends to work best.

When buying extracted kief at a dispensary or retail store, keep in mind that the purer the kief, the lighter the color will be. Kief that still looks fairly green means that there is still quite a bit of plant matter mixed in, whereas kief that has been well cleaned tends to be more of an off-white color.

What’s the Deal with Hash?

Extracting kief is one of the first steps of making hash. To simply summarize, hash is basically just kief that has been heated and pressurized to form a soft, green ball. Applying heat and pressure to kief changes its composition by rupturing the resin glands. Once the kief ruptured, the overall taste and effects of the product are slightly different. Pressurizing kief also darkens its color; the more pressure you apply, the darker the hash becomes.

Kief may not be the most exciting cannabis product out there, but it still remains one of the most popular and easiest to access. For more information on kief and kief extraction, check out Ed Rosenthal’sBeyond Buds. In the meantime, be sure to pick up a three-chamber herb grinder if you’d like to get the most bang for your buck.


 

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Cold and Heated Cannabis Extractions

Medical cannabis is processed for administration in various ways; fresh, dried, and cold/heated extractions (or concentrates). In this session of the Substance Cannabis Class, we will be covering the different forms of cold and heated extractions.

Cold extractions/concentrates result in various products: 

  1. Kief: Powder of the trichomes that have fallen off the plant. May be ingested raw but is usually smoked on top of flower buds or ingested in cooked edibles.
  2. Slurry: Extraction using olive oil or alcohol. Usually ingested raw.
  3. Hash: Extraction using cold water and ice. May be ingested raw, smoked or used in cooking. Variety names reflect differences in the proportion of plant material to trichomes and how the variety reacts to heat.
    • Bubble = initially bubbles when exposed to heat.
    • Full bubble = continues to bubble throughout the heating process.
    • Melt = melts or turns into gooey oil when exposed to heat.
    • Full melt = almost pure trichomes; fully melts when exposed to heat, leaving little or no residue.
  4. Wax: Extraction using a solvent, most commonly butane, propane, CO2 or O2. Removal (“purging”) of the solvent may be through cold or heat evaporation (which changes the compounds available). Waxes are usually burned or vaporized, but may be used in cooking and in topical salves. Variety names usually refer to consistency. Examples:
    • Honeycomb/Crumble = dry, crumbly texture; often has small holes like a honeycomb.
    • Budder = more viscous, consistency like butter.
    • Shatter/Glass = consistency similar to hard candy.
    • Sap = sticky texture similar to honey.
    • Taffy = firmer than sap but not brittle like shatter.

Heated extractions/concentrates convert the cannabinoid acids into their neutral forms and usually removes most of the terpenoids. Various products include: 

  1. Tea: Extraction into hot water and then drunk.
  2. Tincture: Heated cannabis that is extracted in alcohol. Usually administered directly under the tongue (sublingually).
  3. Edible: Extraction into a fat (butteroil) and then used in cooking food.
  4. Oil: Slow heating of cannabis in olive or coconut oil. Usually used in food or topically on skin.
  5. Salve/Cream/Lotion: Low heating of cannabis oil with beeswax. Used topically on skin.