Rosin is a cannabis concentrate that is extracted from trichomes mechanically using heat and pressure. The process can be likened to squeezing the juice from a fruit. It results in a pure, high-quality product that is free from residual chemicals. Rosin is often referred to as solventless hash oil (SHO) because it is extracted from the plant material without the use of solvents.
Rosin pressing differs from solvent-based extraction methods that use hydrocarbons, alcohols, or supercritical CO2 to dissolve the active compounds from the plant. Although solvent-based extraction is the standard for large-scale commercial operations, rosin is becoming increasingly popular among cannabis enthusiasts who are looking for cleaner and more environmentally friendly options.
Moving toward solventless extraction allows cannabis concentrate manufacturers to appeal to high-end customers. Rosin is typically perceived as clean, artisanal, and top-quality, and sells at a premium price.
Why Is Rosin So Popular?
Rosin is popular with extractors because of its ease of fabrication. While it can be made safely with equipment as simple as a hair straightener, high-grade professional equipment produces higher yields and more consistent results.
The need for greater consistency at scale is what inspired us to launch our own solventless extraction equipment company. Our American-made rosin presses take the concept far beyond the industry’s rudimentary beginnings with recipe-driven controls and modular designs. This allows extraction professionals to offer top-notch products with engineering precision.
By incorporating advanced technology and all-in-one workflows, our equipment enables cannabis extraction professionals to achieve the gold standard: a product that is free of chemicals and boasts a clean terpene and cannabinoid chemical profile. The output (presuming premium starting material) will delight medical and recreational consumers alike.
Chemical Processes in Rosin Extraction
The science behind rosin extraction revolves around the use of heat and pressure to melt and then isolate the resin contained in cannabis trichomes.
What Is a Trichome?
Trichomes are tiny glands that house most of the chemical compounds in the cannabis plant that we are interested in. This includes cannabinoids like THC and CBD, as well as terpenes that provide the flavors and aromas. Trichomes are found most abundantly on the flowers and sugar leaves.
What Happens Inside a Rosin Press?
When plant material is placed under the heated pads of a rosin press, a physical reaction occurs:
- Liquefaction: Heat softens the trichomes' waxy cuticle, forcing the resin inside to liquefy.
- Mechanical separation: High pressure forces the liquefied resin out of the trichome head (and out of the micron bag onto the parchment paper).
Preserving the qualities of these chemical compounds is what ensures high-quality rosin. A top-grade rosin press will ensure that your temperatures and pressure are precise. This prevents excessive heat and pressure from creating a lower-quality product due to chlorophyll contamination, terpene evaporation, or burning. Or conversely, insufficient heat and pressure leading to low yields.
Different Types of Rosin
The various types of rosin are differentiated by the starting plant material used in the process. Although rosin can be extracted from many different materials, including hemp, the main categories are flowers, hash, and kief (or dry sift).
Flower Rosin
Flower rosin is extracted from dried and cured cannabis flower. This is the most common form of rosin among hobbyists and home extractors due to the simpler steps involved in the process.
All that is needed to make flower rosin is cannabis flowers (at optimal humidity levels), a correctly sized micron bag, and a rosin press. It is recommended to break the flowers into popcorn-sized pieces and remove any twigs or stems before pressing.
Temperature and pressure for flower rosin extraction tend to be higher, as the resin is released with less ease than it is from more processed materials.
Hash or Bubble Hash Rosin
Hash or bubble hash rosin requires washing the flower heads in ice water to separate the trichomes, then drying before pressing. This rosin type is preferred by industry professionals, as it results in a cannabinoid and terpene-rich product with a much higher market value.
Live Rosin (From Live Bubble Hash)
Live rosin is extracted from bubble hash made from fresh plants that are immediately frozen after harvesting. This allows many of the characteristics of the “live” plant to be preserved. The live bubble hash is then used to make live rosin with the chemical profile of living cannabis. Live rosin is considered to be the pinnacle of rosin products.
Dry Sift and Kief Rosin
Rosin can also be extracted from kief. However, this is not usually standard in commercial extraction. It is more typically performed ahead of infusing rosin in edibles or topicals. Dry sift is made from resin heads that are separated mechanically from the plant using a graduated series of mesh screens. As such, it is a more refined version of kief.
Differences Between Rosin, Resin, and Distillate
Rosin, resin, and distillate are all cannabis concentrates. However, they vary in potency and flavor, and cater to different tastes. The main differences between rosin, resin, and distillate lie in the extraction method and the resulting chemical profile.
- Rosin (including live rosin): This is the “cleanest” of the cannabis concentrates and is obtained solely through thermal and mechanical processes.
- Resin (including live resin): This concentrate is obtained through chemical or solvent-based extraction, usually using butane or propane. Although a common and popular product, the process of eliminating chemical residues needs to be rigorous.
- Distillate: As its name implies, this cannabis concentrate is obtained through molecular distillation. The result is an oil that is often stripped of terpenes and other chemical compounds, leaving an isolated cannabinoid (most often THC).
Cannabis Plant Extract Comparison Table
|
|
ROSIN |
RESIN |
DISTILLATE |
|
Extraction Method |
Solventless |
Solvent-based |
Fractional distillation |
|
Purity |
Solvent-free |
Purged of solvents |
Highly refined |
|
Potency (THC) |
60-80 percent |
65-90 percent |
90-99 percent |
|
Flavor |
Full-spectrum |
High |
Neutral |
How to Obtain High-Quality Rosin
Obtaining high-quality rosin requires finding the perfect balance between temperature and pressure, as well as time on the rosin press. The quality of the initial material and your solventless extraction equipment will determine the outcome. A high-grade rosin press allows for consistently high-quality results, in line with market standards.
To read more about how to master the use of a rosin press to obtain the best results, read our guide: How to Use a Rosin Press.
Storing and Curing Rosin for Terpene Retention
Preventing the breakdown or loss of rosins' volatile molecules with proper post-extraction handling is essential for a long-lasting, quality product.
Storing Rosin
Rosin is unstable at room temperature. Refrigerating and storing it in an airtight container will stabilize it in the fresh press stage. However, playing around with curing and refining techniques allows for a more diverse product.
Rosin Curing for Specific Consistencies
Curing will allow you to create rosin SKUs that are more “finished.” Manipulating temperatures after pressing your rosin allows you to create varying textures and consistencies.
- Cold Cures and Budder and Badder Texture: Cold curing involves storing your rosin in an airtight container (Jar Tech) at low temperatures (maximum 70 degrees Fahrenheit). The product is whipped regularly to encourage nucleation. This results in a buttery consistency and a more stable product with an increased shelf life.
- Warm Cures and Jam and Sauce Texture: Warm curing involves placing your rosin in a sealed container at higher temperatures (120 degrees Fahrenheit). The heat causes the terpenes to separate in liquid form while the THCA crystallizes. This creates a consistency known as jam or sauce rosin.
THCA Isolation
Placing the rosin back into a fine micron bag and applying high pressure with very low heat will allow the terpenes to be squeezed out, leaving behind white, powdery crystallized THCA in the bag. This THCA isolate is often used alongside other cannabis extracts and products to boost their potency.
How Rosin Is Consumed
Rosin is most often consumed through dabbing or vaping. Because rosin smoke is rich in volatile chemical compounds, consumers typically use low temperatures to preserve the flavor profile of the rosin. Rosin can also be decarboxylated and infused into edible and topical products.
- Dabbing: The rosin is flash-vaporized using a quartz banger on a dab rig (a specialized water pipe). This limits combustion-related carcinogens and allows the user to benefit from the full spectrum of the plant’s chemical profile.
- Vaping: Liquefied rosin can be vaporized using a vape pen. The rosin must first be decarboxylated so that it remains in a liquid state. This process converts the THCA to THC, lowering the viscosity of the cannabis oil so it can flow through the vape atomizer.
- Edibles and Topicals: Decarboxylated rosin can be infused into edibles and topicals, typically through emulsion techniques.
Rosin FAQs
Is rosin stronger than resin?
Chemical solvent extraction tends to be more aggressive than solventless extraction, resulting in resin sometimes having higher THC levels. However, rosin is considered stronger due to the “entourage effect” of preserved terpenes and other cannabinoids that work together to create a more potent, full-spectrum experience.
What is the difference between live and cured rosin?
Live rosin and cured rosin are extracted from two different types of starting material. Live rosin is made from fresh plants that are frozen at the time of harvest, capturing the “living” chemical profile of the plant. Cured rosin is made from dried and cured flowers. This allows for a complex flavor but lacks the volatile terpenes found in live rosin.
Note: The sense of “cured rosin” with regards to starting material is distinct from performing a cold or hot “curing” step after extraction. You can have live rosin that is consumed fresh or subsequently “cured” after pressing, and also cured rosin (from dry starting material) that does or doesn’t go through a “curing” step after extraction.
What is the melt test for rosin quality?
In commercial circles, the quality of rosin is tested by how it melts on a quartz banger. Top-quality rosin will leave no residues or char behind. If dark deposits appear, this indicates that the rosin has material residue, meaning that the extraction process was less precise.
The Future of Rosin in the Cannabis Industry
As the cannabis industry moves toward the “clean label” trend, solventless extraction is becoming the go-to approach for quality cannabis extracts. By preserving the unique chemical profiles of the plant, rosin offers a product that is both potent and healthy.
According to a study published on ResearchGate, solventless extraction methods are the best way of preserving the complete biochemical profile of the cannabis plant. As a professional in the industry, understanding and mastering the art of rosin and solventless extraction will ensure you keep up with the market and provide consistently high-quality, true-to-the-plant products.
