What is an Essential Oil

An essential oil is the oil of a plant from which is was taken. For example lavender essential oil is the oil of the lavender plant.

The word essential means essence and therefore it is the oil part of the plant. The oil is extracted from the plant either by distillation, expression or by using a solvent. The distillation process involves putting the plant over some water. The steam passes through the plant and the oil becomes vaporised. This vapour is collected and becomes the essential oil.

Plants which often undergo this process are lavender, peppermint and eucalyptus.

The water that is used to vapourise the plant is sometimes kept and used for fragrances.

Expression is the process which was used before distillation was discovered and is still used for citrus peel, where the product is just cold pressed until the oils are extracted. Solvent extraction is used for most flowers because their oil content is too low for distillation to work.

Hexane is used to extract the wax and oil  (in the same process used to remove caffeine from coffee) and then further processing is done to eliminate the alcohol and wax.

The plants chosen tend to be very fragrant and are thought to have some sort of healing property or other health benefit.

For example eucalyptus oil which is the most commonly used essential oil worldwide is used as a disinfectant in some countries and for unblocking sinuses as well as being used in medicines as an anti bacterial and anti inflammatory.

Rose oil is also a very common essential oil and is not used medically but for perfumes and other scents.