There are so many different ways to extract essential oils from the plant material
“A pure essential oil is a vibrant, dynamic liquid which almost seems to have life quality of its own” Robert Tisserand.
With such a vast selection of plant parts to extract essential oils’ from, there are several different methods used for extraction. The most common methods include:
- Steam Distillation
- Solvent Extraction
- Cold Pressed (Expression)- Citrus
- Enfleurage
- Co2 Extraction
Steam Distillation
One of the most common methods for distilling essential oils is Steam distillation. This method uses steam to extract essential oils from its plant material. The material is suspended over water in a sealed container, which is then brought to a boil. The steam which contains the volatile essential oil is then run through a cooler. This again condenses the liquid that is collected. You can visibly see a thin layer of essential oil appear on the top of the liquid, as water and essential oils do not mix. The water and essential oil are separated as the final oil are collected in a small vial, while the hydrosol floral water runs into a large vat.
Solvent Extraction
Solvent extraction uses little heat to preserve the oil (that would otherwise be destroyed or altered during steam distillation). Fragrant plants such as Jasmine, Hyacinth, Narcissus, or Tuberose with fragile plant material are dissolved in a liquid solvent of either heptane, hexane, or methylene chloride as a suitable perfume solvent. The solvents absorb the smell, color, and wax of the plant. After the plant material is removed, the solvent is boiled off under a vacuum to separate the essential oil. A substance called ‘concrete’ remains once the solvent evaporates. The concrete is mixed with alcohol to aid in the filtering of waxes when distilling the alcohol away, which leaves an ‘absolute.’ You will see the word ‘absolute’ on the label of some bottled essential oils. It is important to note that an absolute may contain 2-3 percent of the solvent; therefore, it is not considered pure essential oil.
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