Learn About Essential Oils #4 - Distillation Methods

The following are the methods that are used for distilling EO's with a brief description: (we will be learning more about this as the course progresses.)

(These definitions are taken from Dr. Kurt Schnaubelt's Aromatherapy Course book.  Dr. Schnaubelt is one the world's foremost authorities on EO's and heads up the Pacific Institute of Aromatherapy. The more complete definitions are in his book.)

The Basic Distillation Methods Are:  Water and/or Steam Distillation, Cold Pressing and Extraction

Water Distillation:  The plant material is placed in the still and is completely covered with water.  All is brought to a boil.  This is one of the oldest forms of distillation, kind of like making an herbal tea.  It is the most generally acceptable for aromatherapy use because it is economical and because water is the only substance that comes in contact with the oil, it is free of contaminants.

Water and Steam Distillation:  Same as above, only in this process live steam is generated in a separate apparatus and then led through the still.

Steam Distillation:  Plant material is placed on a large grate and steam (often over-heated) is injected into the dry material.  This method is employed mostly for industrial production of EO's.

Cold Pressing:  Used exclusively to prepare citrus oils.  Very gentle.  The peels are separated from the fruits and then cold pressed.

Extraction:  For raw materials with low concentration of EO's, (like Jasmine).  In extraction a 2-step process is used whereby a volitile solvent is used first and then evaporated leaving a solid mass called a "concrete".  In the second step the concrete is heated and then cooled and filtered.  What remains is called an "absolute".

Extraction with Enfleurage:  Done cold or hot, this is extraction with animal fats. The method was used for ages for delicate fragrances but now is practiced only with Jasmine and Tuberose.\

Extraction with Carbon Dioxide:  This is a new form of extraction employs the behavior of liquified gases.  Oils can be extracted at very low temperatures.  This method has made possible the only successful extraction of Lilac and Lily of the Valley.