Q.How Are Essential Oils Extracted?
Essential oils are highly concentrated components extracted from plant matter: flowers, fruit, leaves, resin, twigs, seeds, or roots. There are four ways essential oils are currently being extracted:
Steam distillation is the most common method of extracting the essential oil from plant matter. This method involves steaming the plant matter of choice for a determined amount of time, under a specific pressure, and at a certain temperature so as to release the oil. The oil collected is now officially an “essential oil”, and the remaining water is sold as a “hydrosol”.
This method is similar to steam distillation, only liquid CO2 is used instead of water. After the liquid CO2 and the plant matter combine, the CO2 is turned back into a gas, leaving the plant matter and essential oil behind. This provides a different, more pleasant, aroma than you would get from steam distillation, and is often the preferred method of extraction.
Expression, or cold pressing, is used primarily for citrus fruits like orange and lemon, where the essential oil is obtained in tiny pockets in the peel or rind. Oils extracted by cold pressing are the most volatile of essential oils and can evaporate quickly when exposed to air.
Purists don’t consider solvent extractions to be true essential oils, and they are typically labeled “absolutes.” This is due to the fact the plant material, usually flowers, are mixed with a solvent. Sometimes there is a significant amount of solvent left behind in the absolute, resulting in a less-pleasant aroma and lesser-quality end product. Traditional aroma therapists generally avoid absolutes, and don’t recommend them for pregnant women and children.
It is important to note that all essential oils are considered “pure” after extraction, regardless of the quality of the plant matter used.