What Makes An Essential Oil Therapeutic Grade?
Most people read the label on essential oils bottles and see
the words "100% PURE" and think that is a therapeutic
grade oil. There is so much more involved in producing truly
therapeutic grade oils.
The key to producing a therapeutic grade essential oil is to preserve as many of the delicate aromatic compounds within the essential oil as possible. Most of these elements are very fragile and are destroyed by high temperature and high pressure.
Nutritionists tell us not to boil our vegetables because the hot water removes the vitamins and nutrients. Similarly, "boiling" plants to extract their essence destroys many of a plant's fragile constituents, which gives essential oils their therapeutic properties. So keeping the distiller's temperature low is a must.
Distillation can determine the value of the oil, or destroy the value of the oil. Essential oil distilling is not just a job, but an art. The operator of the distiller must have a full understanding of the value of oils in order to produce quality oils. If the pressure is too high, or the temperature is too high, it may change the molecular structure of the fragrance molecule, altering the chemical constituents.
Essential oils MUST be distilled for the proper length of time to release all their active constituents. A distiller who is only interested in profit will distill oils for 15 minutes at very high temperature & very high pressure. This way they can produce more oil and thus more profits.
For example, cypress must be distilled for 24 hours to release all the chemical constituents. Most distilling operations, throughout the world, only distill cypress one hour and 15 minutes.
Similarly, lavender does not produce all its therapeutically effective substances unless it is distilled for one hour and 30 minutes; but most lavender is distilled for only 15 minutes!
Three-quarters of the volume is extracted during the first quarter of the distillation process. Many producers end the process there because the increased time does not significantly increase the volume. Time is "only" a crucial factor to extracting the plant's therapeutic properties. Lavender should be distilled at no more than 3 pounds of pressure, a temperature of no higher than 245 degrees, and should be distilled for 2 hours.
Another trick some distillers will do to produce more oil, is to redistill the plant material over and over as many as 5 or 6 times. It's like using a tea bag over & over again. When the plant material is redistilled, all the batches after the first distillation are no longer therapeutic grade.
The oil distiller will then save the first batch to be sold as therapeutic grade oils. Then the rest of the distillations are sold to the unsuspecting public as so called "pure" oils.
There are many other factors that effect the quality of the oil.
A few examples:
Is the distiller made of chemically reactive metals or was it stainless steel?
Was the soil fertilized with chemical fertilizers or organic fertilizers?
Were any chemicals added to the distillation water?