The process of steam distillation is one of several methods that allows you to extract the essential oil from plants. This technique of oil extraction is the main method used in the fragrance and essential oil industry, because it has the advantage of being the most efficient and cost-effective, and preserves the integrity of the plant oils. The process requires some skill and investment in equipment.
Steam Distillation: The Process
Steam distillation is one way you can extract oil from plant matter. Essentially, you fill a chamber with holes in the bottom for steam to come through with either fresh or dried herbs. A lid keeps the oil from diffusing into the air when the steam is applied to it. You collect the condensed water and oil droplets and channel them through a filter, which separates the water from the oil.
Advantage: Quality Control
People or companies who wish to use steam distillation to extract plant oils might have concerns about the quality of the extract they produce if they plan to use the extract for aromatherapy or medicinal purposes. Steam distillation allows you to control the temperature and amount of steam you apply to the plant material. Keeping the temperature right at the boiling point of water allows for the least amount of degradation to delicate botanical oils.
Advantage: Wide Application
Steam distillation is useful for extracting most fats, oils and waxes. This process works well for types of substances that do not mix with water, which are known as immiscible substances. Because of its wide application to immiscible substances, steam distillation can be a cost-effective method to invest in to extract a diverse array of immiscible substances. Also, because the steam temperature can remain at the boiling point of water, this process also has a cost benefit of requiring less fuel for the steam boiler.
Disadvantage: Higher Equipment and Operating Cost
Steam distillation has the disadvantage of having a higher initial cost for investment in the equipment needed to execute the process successfully. You'll need some initial training in order to operate the equipment, and you must take care in conducting the process because you're working with high temperatures, a heat source, pressurised containers and volatile oils. A final hidden cost to the process is the cost of maintaining and repairing your equipment.