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romatherapy uses essential oils to treat medical conditions or alleviate psychological ailments. The essential oils of aromatherapy have the power to affect both your physical and mental state.

extracted from living plants

Essential oils are extracted from living plants and trees using four different methods: steam distillation, enfleurage, solvent extraction, and carbon dioxide extraction.

Steam distillation is the most common method of essential oil extraction. Steam distillation stills are often kept close to where plants are grown for maximum essential oil freshness. Essential oils are extracted from different parts of different plants. In steam distillation, the appropriate plant parts are compacted into the still. Steam passes through the plant parts and essential oils evaporate into the steam. The oil-laden steam then passes through a condenser where it cools into water and oil. This separates with the oil on top, and the essential oil is then siphoned off.

Some plants (jasmine is an example) do not respond well to steam distillation because the intense heat destroys the delicate odors. Different methods have been devised to overcome this obstacle. These methods technically produce an "absolute" instead of essential oil. Absolutes are more concentrated, but may contain traces of the substance used to extract the absolute.

Steam distillation is the most common method of essential oil extraction.

Enfleurage is a generally obsolete method. Flowers are spread on trays containing a special fat and over time oil soaks into the fat. When the fat is saturated, alcohol is used to separate the absolute from the fat. The fat, which contains residual amounts of the plant absolute, can be used for soap production.

In solvent extraction, plant flowers are mixed with a solvent (hexane is one solvent often used). The mixture is heated, the solvent vaporizes and a "concrete" remains that is half absolute and half plant wax. Alcohol is then used to separate the absolute from the plant wax.

Carbon dioxide extraction is a promising new process. It is similar to solvent extraction, but uses liquid carbon dioxide as the solvent. Under low pressure, the process yields a result much like steam extraction but without heat damage. Under high pressure, carbon dioxide extraction yields a result much like solvent extraction, but without solvent residue.

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