A solventless product is separated from the plant without dissolving it in a chemical solvent. The methods are mechanical: dry sieving (kief, dry sift), agitation in ice water (bubble hash), hand-rubbing (charas), and heat-and-pressure pressing (rosin). Water and ice are used in ice water hash, but water doesn't dissolve cannabinoids, so the industry counts those products as solventless.
In practice
Solventless products include kief, dry sift, ice water hash, full melt, temple balls, pressed hash, rosin and live rosin. Their appeal is simplicity and the absence of residual solvent risk, and many consumers prefer them on taste. Quality still varies widely; solventless doesn't automatically mean clean, potent or free of microbial or pesticide contamination, which come from the starting material. Russo et al. (2021) is one of few peer-reviewed studies on fresh-frozen solventless methods.
Don't confuse with
- Solvent-based extract: uses butane, propane, ethanol, CO2 or similar.
- Solvent-free (marketing): occasionally misused for purged solvent extracts, which are not solventless.
Kief is the loose, powdery collection of trichome heads that falls or is sifted off dried cannabis through fine screens; it is the simplest solventless concentrate.Bubble hash, or ice water hash, is a solventless concentrate made by separating trichome heads from cannabis in cold water and collecting them on graded mesh bags.Charas is hashish made by rubbing the resin off living cannabis flowers by hand and rolling it into balls or sticks, a traditional method of the Himalayan regions.Rosin is a solventless concentrate: resin squeezed out of flower, kief or hash using heat and pressure, then collected as an oil free of plant material.A cannabinoid is any compound that binds the body's cannabinoid receptors or shares the typical cannabis terpenophenolic structure; the plant-made ones are phytocannabinoids such as THCA and CBDA.A temple ball is hash worked by hand into a dense ball and cured over time, a traditional Himalayan style associated with a glossy surface and soft interior.Fresh frozen is cannabis frozen immediately after harvest without drying or curing, used as starting material for live resin and live rosin to keep more volatile aroma.Live rosin is rosin pressed from ice water hash made from fresh frozen plants, preserving more of the volatile aroma of the living plant; it is solventless.Hash is any concentrate made by separating trichome heads from cannabis and collecting or pressing them, from dry sift and ice water hash to hand-rubbed charas.
