Essential oils are a concentrated, hydrophobic liquid that contains unstable aroma compounds from plants. Here’s how essential oils are made.
Many floral scents are made through solvent extraction as the flowers don’t have plenty of volatile oil to be extracted. Their chemical components are also extremely delicate and can be broken down by the extreme heat used in steam distillation. The oil is extracted by using a solvent. The extract is called concretes, which are a combination of waxes, essential oil, resins and other oil soluble plant materials. Concretes are very fragrant, but contain materials that are not aromatic and not required.
A different solvent, ethanol, is used on the concretes which extracts only the aromatic molecules. When the ethanol vaporizes, only a certain kind of oil called absolute remains. Absolutes are more aromatic than essential oils. Very small amounts of the solvents remain in the absolute, so it’s not considered suitable for use in aromatherapy. However, the perfume industry uses these absolutes to create a fresher aroma. Mimosa, tuberose and jasmine essential oils are usually extracted through this process.
Most essential oils are made through distillation. The wood, peel, roots, bark, flowers, leaves and seeds of the plant are put in a distilling apparatus that’s then placed over water. The steam coming from the heated water goes through the raw plant matter and vaporizes the unstable compounds. The resultant vapor passes through a cooling coil that turns it back into liquid, which is then gathered in another container. This liquid is called a plant distillate or hydrosol and may be sold as a fragrance product. Discover more about the process through the information available at OilingPoint.com.
Essential oils can also be obtained through mechanical expression or cold pressed. The fruit rind is ground and pressed to obtain its extract. Most sweet orange and lemon essential oils are made through this method.