Testing for efficacy, purity and consistency of essential oils

Essential Oils

There are several methods that can be adopted for testing the purity of essential oils. Many companies use only one of these methods and don’t go the extra mile. Individual companies have their own protocols and before choosing an essential oil company it is important to research the level of testing adopted.

Gas Chromatography

  • After the essential oils are distilled, samples are tested for chemical composition using gas chromatography.
  • Essential oil compounds are vaporized and passed through a long column called a gas chromatograph.
  • Each individual compound travels at a different rate and is measured as it exits the column during the testing period.
  • This method determines which compounds and the levels of those compounds that are present.

Mass spectrometry

  • Essential oil samples are vaporized then ionized and each individual compound in a sample is measured by weight.
  • The process of mass spectrometry gives insight into the purity of an essential oil – displaying any inorganic compounds such as heavy metals or other pollutants.
  • Pollutants and heavy metals are too heavy to elute along a gas chromatograph.

Infrared Spectroscopy

Every essential oil batch is transported to a filling facility before being released. Individual batches are held in quarantine while additional quality tests are done. A thorough analysis of material composition is carried out. Light is shown at a material sample and the amount of light absorbed by the chemical constituents of the sample is measured. Results are then compared with a historical data base.

Microbial Testing

Before a batch of essential oils can be released for filling it must be tested for biohazards such as bacteria, fungus and mold. Samples are drawn from each batch of oils and applied to growing mediums in petri dishes. After an incubation period each plate is analyzed for growth of microbes.

Organoleptic Testing

  • Human touch – tested with sight, touch, taste and smell. An art form!
  • Adopting all of these methods helps ensure a quality and consistency expected from a pure therapeutic grade essential oil.

Continue reading to learn about blending of essential oils.