Bubble hash is hash made with ice water. Cold makes trichome heads brittle so they snap off the plant under gentle agitation; the heads, being denser, separate from plant matter in the water, and the slurry is filtered through a series of mesh bags graded in microns. Each bag catches a size fraction of heads, which is then dried. The name comes from the way high-grade material bubbles when heated.
In practice
Hash makers describe grades by micron fraction and by melt quality, often on an informal one-to-six-star scale. The middle fractions usually hold the cleanest, most intact heads; the finest and coarsest fractions carry more debris. Starting material can be dried flower, trim or fresh frozen plants; fresh frozen gives "live" products. Russo et al. (2021) studied a fresh-frozen ice water method and reported that it preserved cannabinoid and terpene profiles well. GenetixBay defines the product but doesn't provide processing steps.
Don't confuse with
- Dry sift: separated with dry screens, no water.
- Full melt: the top grade of bubble hash (or dry sift), not a separate method.
- Rosin: may be pressed from bubble hash, but is a further product.
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.Trichome heads are the bulbous resin-filled tops of capitate glandular trichomes, where cannabis makes and stores nearly all its cannabinoids and terpenes; they are the raw material of hash.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.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 terpene profile is the measured mix of terpenes in a sample, reported as each compound's % w/w and the total, used to describe and compare cultivar aroma chemistry.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.Full melt is the highest grade of solventless hash, so pure in trichome heads that it melts almost completely with little or no residue when heated.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.Micron bags are fine-mesh filter bags graded by opening size in microns, used to separate and size trichome heads in ice water hash making and to filter rosin.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.Solventless describes cannabis concentrates made only by mechanical or physical separation, using screens, ice water, heat or pressure, without chemical solvents.
