What does a herb distiller do?

A herb distiller is a person or machine used to extract essential oils from plants and herbs with the help of steam or water through the process of distillation. Distillation is a process of separating components of a liquid mixture by selective evaporation and condensation.

There are two common methods of distillation: simple and steam. In simple distillation, the plant material is placed in a still and heated until the volatile oils vaporize. The vapor is then condensed back into a liquid, which is collected as essential oil. In steam distillation, steam is passed through the plant material, carrying the volatile oils with it. The steam and oil vapor mixture is then condensed back into a liquid, from which the essential oil can be separated.