Facts on Essential Oils

Essential oils are the volatile oils extracted from various parts of plants, flowers, fruits and trees. They are used extensively to add flavor and aroma to a number of products. Using essential oils to treat illnesses and conditions, called aromatherapy, can be traced back thousands of years.

Historical Roots

Essential oils for purification and medicinal uses can be traced all the way back to ancient China. According to Julia Lawless, author of "The Illustrated Encyclopedia of Essential Oils," some of the earliest records of the use of essential oils can be found in the "Yellow Emperor's Classic of Internal Medicine," an ancient Chinese manuscript outlining some of the oldest practices of Eastern medicine dating from more than 2,000 years BC.

Description

Essential oils are not actually oils. According to Biology Online, an essential oil is a plant product, usually somewhat volatile, giving the odors and tastes characteristic of the particular plant and thus possessing the essence. Most essential oils, such as lavender and orange, are thin and liquid. Some, such as vetiver and oakmoss, are thick and sticky.

Plant Origins

Essential oils are extracted from botanicals from around the world. The precious elixirs are taken from the stem, seeds, bark, sap, resin, leaves, needles, fruit, flowers and leaves of trees, bushes and flowers from most of the seven continents. For example, Scotch pine essential oil is extracted from the needles of the tree that grows native to Eurasia, and is cultivated in the U.S., Russia and Finland. Black Pepper essential oil is extracted from the peppercorns and is native to southwest India. It's cultivated in many tropical countries, including Indonesia, Malaysia and Madagascar.

Extraction Methods

There are many ways to extract the oils from the plant. According to Lawless, the method of extraction depends on the quality of the material used and the type of aromatic product that's required. For essential oils, the most common ways the oils are extracted are by simple expression or pressure, and steam, water or dry distillation. Most oils are produced by steam distillation, whereby only the volatile and water-insoluble parts of the plant are isolated from the other constituents.

Common Constituents

Some essential oils can contain hundreds of constituents. Most contain a blend of chemicals that can cause pharmacological, physiological and psychological responses. The most abundant chemicals found in essential oils are terpenes, aldehydes, alcohols, esters, phenols, ketones and oxides.