Desirable cannabis components like kief, hashish and rosins can be prepared without solvents.
Kief refers to the tiny, sticky, white crystals covering the cannabis flower, otherwise known as the resin glands/trichomes. They contain the largest amount of the active terpenes and cannabinoids. The purpose of trichomes is actually to deter predators in the wild. Extraction of kief is a very simple process. It can be separated from cannabis buds simply by grinding and sieving. When separated from cannabis inflorescence, kief looks just like a powder or pollen. And, as cannabinoids and terpenoids are particularly concentrated in trichomes the powder can be added to cannabis preparations to boost potency or consumed alone as a standalone product.
Traditional hash, or hashish, is another example of a solvent-free cannabis extract. The goal is to separate the trichomes from the plant material as they contain the highest concentration of desirable compounds. Two main methods exist for creating hash: one involves taking frozen cannabis buds and breaking them into smaller and smaller parts over a screen. In the process, trichomes are separated from the plant and fall through the sieve and then pressed into blocks. The other primary method of solvent-free hash extraction involves using ice water to separate the trichomes from the bud. After drying they can then be pressed in a hash block.
Rosin has also become very popular in recent years. Produced from flowers, hash or kief, rosin is a translucent substance typically with a sap-like consistency. The rosin extract is made by applying heat and pressure to the material you wish to extract from and results in a product that’s very similar to the more time-consuming, expensive and, solvent-based butane extraction. Analytical testing has demonstrated that this simple approach effectively extracts cannabinoids and terpenes with absolutely no risk of leaving behind toxic residual solvents like butane.