Resin and rosin have become well established and highly sought-after cannabis products in today’s market, but they are commonly confused, yet the products come from two polarizing extraction techniques: hydrocarbon extraction and solvent-less extraction via pressing.
What is Resin? What is Rosin?
Technically, rosin is resin, and so is pretty much any other cannabis oil that is extracted. Whenever we extract from cannabis, we are extracting resin!
Cannabis resin is produced in the glandular trichomes of the cannabis plant and appears as a sticky sap, which is a natural by-product of the cannabis plant and acts as an immunological defense mechanism against insects and other foreign invaders. This resin is packed with high concentrations of cannabinoids, like THC, but even more important than that are the high levels of terpenoids and flavonoids it contains. The combination of these phytochemicals is what we are after to produce an aromatic, flavourful, and synergistic high experience.
In contrast, the word rosin is describing the process by which we are extracting the resin. This is what we refer to as rosin pressing, which uses heat and pressure to extract the resin out of the cannabis plant. Even though all cannabis oil is extracted resin, resin has become the catch word for oil produced from hydrocarbon extraction.
Key Manufacturing Differences
The key to understanding the difference between resin and rosin lies in how each are made.
The glaring difference between resin and rosin is that the resin is produced via solvent extraction, specifically using hydrocarbons like butane and/or propane, while rosin is a solvent-less technique using heat and pressure.
Rosin utilizes temperatures of about 65 Celsius to 100 Celsius and pressures of anywhere between 300 and 1,000 psi. We utilize a hydraulic press to apply pressure using preheated plates to, essentially, squish the flower. As it’s being squished and heated, the resin is forced outward from the flower, through the micron bag containing it, and on to the parchment paper. The best flower to use is a fresh cannabis flower or a properly dried or cured flower that contains good moisture.
In essence, we are using a mechanical process to “extract” the resin out, which is what makes it rosin. Once the rosin is produced, it can go straight to packaging or go on to be processed into other rosin variants such wax or budder.
With resin, on the other hand, we use a solvent (traditionally butane), to dissolve the resin and extract it from the plant. The closed loop extractor can keep the butane in a liquid phase and the whole process happens at around -40 Celsius and pressures of anywhere between 20 and 30 psi, which is a very stark difference to rosin.
The cannabis material, which is usually either fresh, frozen buds or dried flower, is loaded into a closed loop extractor and liquid butane is passed through the material, which dissolves the resin from the trichomes and other plant components, and then the solution is pushed into another column where most of the butane is recovered to release the cannabis resin from the collection valve. The butane extracted resin then requires full purging of any residual butane, which is usually done in a vacuum assisted oven.
Just like rosin, the product at this stage can be packaged as it is, or processed into other resin variants such as wax, budder, or crumble.
The manufacturing process for resin sounds more involved, but the process can be partially or fully automated, whereas rosin requires more hands-on care.
This leads to a bit of a price disparity, as high-quality rosin can garner a higher cost per gram compared to resin, but both are the highest quality in extract types because they produce a high-potency refined resin oil that captures the terpenes and flavonoids that consumers want.
Tips For Talking About Rosin
When the processes are done correctly and with care, both rosin and resin capture the essence of your favourite strains and elevate them to another level. THC, terpenoids, and flavonoids can be fully captured with both processes and are critical to the well-known effects that come with certain strains, which some consumers gravitate toward.
It’s also important for consumers to know how to use them. The best way to consume rosin (or resin) is to use what is commonly called a dab rig with an e-nail or smart nail. This allows the user to heat the e-nail to the precise temperature they want to take advantage of the product’s full terpene and flavonoid profile, typically between 157 and 232 Celsius. Higher temperatures will combust these fragile compounds, instantly causing a “burnt” flavour.
Rosin can also be rolled into a joint, infused with carrier oils to be added to food, or consumed with a traditional bong or dabber, but temperature is harder to control this way.
The key is to make sure customers understand that the main difference between rosin and resin is the extraction process.
Both are safe and both can be equally amazing, but if customer wants a solvent-free or natural product, rosin is the recommended product. Both have a high capture rate of the full terpene profile, flavonoids, and cannabinoids, which cannot be said of ethanol and CO2 based oils.
Last, but not least, remember that “the higher the THC the better” is not a good gauge of a high-quality rosin or resin product. A rosin product that has 67% THC and a comprehensive terpene profile will never beat the experience of an 80% cannabis oil with little to no terpenes—not on flavour, experience or high, which is why rosins and resins are so highly sought after.
JC Elkhouri is Director of Post Refinement at Sundial Growers.