The rosin technique is rapidly gaining in popularity as a safe, quick and effective method of extracting the active resins from cannabis flowers for medicinal or recreational purposes. Typically, extraction of cannabis oil requires the use of a solvent such as butane, isopropyl alcohol or coconut oil to dissolve the sticky resins and separate them from the plant material. However, the rosin technique removes the need for such solvents, simply replacing them with gentle application of heat and pressure to melt and release the resins.
What Is the Rosin Technique?
The rosin technique is typically used to extract small amounts of resin for immediate personal use, and it is performed using a pair of simple ceramic hair straighteners to provide the required heat and pressure; however, some producers are now using industrial heat presses in order to scale up production and process much larger quantities at once.
The heat and pressure generated by pressing a warm pair of hair straightening irons against a small quantity of cannabis is sufficient to melt the resins and release them from the plant matter to which they are attached. Protecting the cannabis with unwaxed parchment paper shields the cannabis from the straightening irons and also provides the perfect surface on which to release the cannabis oils.
What You Will Need
Along with a set of ceramic hair straighteners (ideally one with a digital temperature control), the simple try-at-home method requires only some standard unwaxed parchment paper. Also advisable is the use of a 25-micron screen, which is placed between the paper and the cannabis, allowing the resins to pass through but not the plant material; and a razor blade or similar implement to collect the resin together once extracted.
First, heat the straightening irons to 200 - 340°F (93 - 171°C); while they are heating, grind or otherwise break down your flowers and separate them into piles of around 0.5g each.
Next, cut or tear the parchment paper into squares large enough to accommodate the individual piles of ground-up cannabis.
Then, place one of the piles of cannabis neatly onto a small section of the 25-micron screen, and fold the screen over once, enveloping the cannabis within it. Fold the parchment paper over the screen so that it entirely envelops the section containing the cannabis. If not using a screen, the cannabis can be placed directly onto the parchment paper.
Once the straightening irons have reached the required temperature, gently place the flat irons around the parchment paper and close them, applying light pressure for around five seconds before releasing and removing them.
Open the paper and peel it gently away from the screen, or directly away from the ground-up bud if not using a screen. A pair of needle-point tweezers may also assist in this stage of the process, to ensure that all oil is retained and all residual plant material removed.
Repeat the process for each of the 0.5g piles of cannabis, using a new square of parchment paper each time.
How to Use your Rosin Hash
Once you have processed all of your cannabis, use the razor blade to scrape all the resin from the squares of parchment paper and collect them together. The final amount of oil extracted from your starting material depends greatly on the quality and nature of the material; if using good-quality flowers, the yield should be comparable to conventional solventless extraction methods at around 10 to 15 percent. The rosin technique is also a popular way to turn hash and kief into oil; if using this type of starting material, expected returns may be much higher.
Once you have collected all of your rosin together, it can be stored and used just as any other extract. rosin has the added advantage of containing more activated cannabinoids than oil extracted from many other solvents, due to the heat used during the production process. Thus, if using rosin to make edibles and tinctures, it is unlikely to require much further heating to entirely activate the cannabinoids within it.