When considering which type of extraction system to invest in, it’s useful to understand what extraction is – and what solvents are. Basically, extraction refers to the process of drawing compounds and oils from raw plant matter into another substance – a solvent. During steam distillation – an ancient form of extraction that many DIYers still implement – raw plant matter is permeated with steam, which draws essential oils and compounds from the botanical plant. Once the steam cools, the condensation left over is used as the extraction. Steam distillation requires high heat, so this practice is best implemented with hardy plant matter that isn’t damaged by high temperatures.
Supercritical extraction, on the other hand, represents the latest craze in the botanical plant extraction realm. Pressurized Carbon Dioxide (CO2) isolates key components of a botanical plant, drawing them from the raw plant matter. Supercritical, or CO2, extraction, though costly to implement, is appealing to some because the process is conducted under low temperatures – ideal for delicate, heat-sensitive plant matter.
Alcohol – namely ethanol – extraction remains the most popular of the three, probably because it’s clean, cost-effective, and makes for a potent end product. In ethanol extraction systems for botanical plants, plant matter is fully dissolved, then purified through a distillation process. A secondary distillation removes the alcohol, leaving only the concentrated, desired key components behind.