Introduction to Essential Oil Distillation
Note: For an in-depth review of the latest high-tech distillation methods, like CO2's and SCO2's, see our comprehensive articles: Making Essential Oils - Steam Distillation, CO2's and Absolutes
The very essence of Aromatherapy is its essential oils. Extracted from a number of aromatic plants, these oils are highly volatile, as well as concentrated. Being highly volatile, these essential oils evaporate fast, leaving no residue, or oily feel, behind. Parts of the aromatic plants, such as flowers, leaves, and stems, in addition to their barks, fruits, and also their roots are used to extract the essential oils. Though the oils are extracted from the aromatic plants by various methods, the most popular and common process is by distillation.
The Process Of Distillation: There are a number of distillation processes through which essential oils are extracted from aromatic plants. The Steam distillation and the Water distillation are two of the methods among many others. Of these two, the Steam process is more popular. Many are of the view that this is the only way to extract essential oils for aromatherapy.
The Steam distillation process requires close monitoring to ensure that the steam is maintained at a temperature that will not cause the plants to be damaged. For the purpose, a still is used which has a vessel for heating, and another one for cooling. After placing the aromatic plant in the heating vessel of the still, steam is introduced into it. The steam helps release the aromatic molecules and oils of the plant. These aromatic molecules, along with the steam, rise into the cooling device, which is cooled by cold water.
The aromatic vapors condense into liquid on cooling. This mixture of oil and water (oil from condensed aromatic vapors, and water from condensed steam) is collected in another vessel. As is the nature of oil and water they are automatically separated ? oil at the top and water at the bottom. The oil from the top is simply siphoned off. This oil is highly concentrated, and is used in aromatherapy in this form.
For the water distillation process too, a still is used. In this instance, the aromatic plant is placed in it and sunken in water. The water is boiled, which helps release the aromatic molecules and oils of the plant ? as in the case of stream distillation. The aromatic vapors are cooled and then easily separated from water. This method of extraction of the aromatic oils is appropriate for plants that cannot withstand high temperatures and pressures.
One method of distillation is the combination of steam and water. In this process, the aromatic plant is placed in a still and submerged under water. Steam is then introduced to help release the aromatic molecules and oils of the plant. On cooling, the essential oils are collected as explained above.
The aromatic oils extracted by the above methods produce essential oils in their concentrated forms. In case of topical aromatherapy, these oils are never applied to the skin in their concentrated forms. They are diluted with the help of carriers, such as alcohol, lotions, vinegar, or water.
It is essential that the essential oils be stored with care. Properly airtight dark bottles, need be used, and should be away from exposure to high heat and temperatures.