Most essential oils worldwide are produced for the flavor, fragrance, and toiletry industry. Because this industry has no need for a natural product these oils are commonly industrially processed. Nature - identical synthetic substances or other compounds not originating from that plant are commonly added.
We strongly recommend that you use essential oils that are produced for aromatherapy only.
Therapeutic Essential Oils For an essential oil to be useful therapeutically it must be very high quality. This depends upon the climate and geography of where it is grown, who the farmer is, what kind of farming methods he or she uses, how the plant was harvested and how the oil was distilled.
Many flowers like violet, gardenia, freesia or lilac are not available in essential oil because they are too delicate for distillation, too expensive or spoil too easily. Artificial oils may smell surprisingly real to an untrained nose, but they are not therapeutic. The best way to make sure of purchasing a true essential oil is to read the label, ask questions and find a company that is trustworthy.
Ask your retailer what he knows about the supplier:
Is the country of origin known?
Does he know the botanical species?
From which part of the plant the oil was distilled?
How was the oil produced?
Ask about the Extraction Methods used in producing an essential oil:
Steam distillation Most essential oils should be steam distilled. During distillation the fragrant plants are exposed to steam until the essence evaporates. The oil-laden steam then rises through tubing where it is cooled. When the steam condenses the oil is found floating on top of the water and can be easily separated out. Master distillers know the right pressure, temperature and duration for each kind of oil.
Cold pressed Citrus oils are often cold-pressed to derive a better aroma. The peel is shredded and then mechanically pressed. It is filtered or passed through a centrifuge to skim the oil off the top of the liquid. Because many growers spray pesticides directly on the peel, it is important to look for organic, cold pressed citrus oils.
CO2 extracted Oils like Coriander and Ginger which are made from dried plant material, are sometimes extracted under pressure, using liquid CO2.
Absolutes Blossoms which are too delicate to withstand high temperatures, are sometimes extracted by solvents. Jasmine and Rose are sometimes solvent extracted. The plant material is put in a solvent like Hexane. The solvent is then removed by evaporation, the product is mixed with alcohol to remove waxes, then distilled to remove the alcohol. Absolutes retain a miniscule trace of solvent.
Excerpt from: "Aromatherapy for Every Day" by Christoph Streicher and Karla Christensen.
