Although essential oils are commonly used in the practice of aromatherapy, questions often arise over both their authenticity and validity for therapeutic use.
Which chemical components go into the make-up of an essential oil and how do scientists prove the existence of these components?
What are Essential Oils?
Essential oils are drawn out of various parts of plants by a process of extraction or steam distillation.
An essential oil is the aroma of the plant, and is contained in the tiny glands, sacs, and/or hairs of the plant.
This aroma is used in the practice of aromatherapy for various therapeutic benefits. Not all plants possess an essential oil – and some that do possess an essential oil are unsuitable for therapeutic aromatherapy practice, which disperses the essential oils through massage, cosmetic products, bath products, and diffusers.
Essential Oil Quality Testing
There are a number of accepted tests which scientists use to test for individual chemical components of essential oils. Not only do scientific tests of essential oils verify the chemical components of an essential oil, they are tests of quality too. For example, some companies may try to pass off a fake essential oil as a pure essential oil by duplicating the scent of the oil with lesser components that do not hold the same (or any) therapeutic value; this process is known as adulterating an essential oil. However, scientific testing shows which chemical components exist within a particular oil – and if these components match what is expected for a particular oil. The two most common methods for scientific testing of essential oils are GC-MS and GLC testing.
GC-MS Testing of Essential Oils
Gas Chromatography-Mass Spectrometry (GC-MS) testing of essential oils is one of the more expensive scientific tests for essential oils. However, many essential oil distributors and aromatherapists use this particular test over others to compare the authenticity of an essential oil because it is a more advanced version of the gas liquid chromatography (GLC) quality test (see below). A reputable essential oil supplier provides reports of the GC-MS analysis of an essential oil to demonstrate the quality and purity of the essential oils they are supplying.
In GC-MS testing, a mass spectrometer is attached to a gas chromatograph. The essential oil molecules that emerge are subject to high energy electrons which separate out the individual components. This allows scientists to identify the individual component by comparing it to the molecular mass spectrum of the essential oil.
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