Sunday, March 10, 2013

Essential Oils 101 continued :-)

You should probably re-read my previous post about the challenges of harvesting essential oils. The many variables explain why one oil, even when harvested from the same place, by the same person, can have a very different chemical composition.

This explains a few things. One, why some oils are so much more expensive than others. Not all plants yield the same amount of oil. Rose oil, for example: you need 60 roses to get one drop of rose essential oil!! (For a fascinating look at rose oil, you can read Wikipedia, here:  http://en.wikipedia.org/wiki/Rose_oil    Because of the large volume of plant matter needed, and, the care and difficulty expended to get it, pure rose oil is very, very expensive.  Paying $60 for 5 ml (one teaspoon!) would be quite acceptable.

Other oils are more forgiving.  Five pounds of peppermint leaves will yield one ounce (30 mls, or 2 tablespoons) of essential oil. A more reasonable price here would be approximately $15 for 15 mls....three times as much oil as rose, for 1/4 of the price!! So we can tell you one thing for certain:

Rule #1 - Essential oils should all be priced separately. There is no way you can price an entire line of essential oils the same price, as, the expense of obtaining the oil varies so widely. If you find essential oils to be uniformly priced, beware!!!

Unfortunately, what some oil sellers do, is take a tiny bit of the expensive oil, and "adulterate" or add a less expensive oil to it. For example, rose geranium smells a bit like rose, but, it is much less expensive. Unless your nose can smell the addition (and most of us can't) you may not be getting what you think you are getting. It is even possible that the expensive oil is adulterated by adding something completely foreign, like vegetable oil, or solvents. This means there always exists the chance that you are not getting a "pure" essential oil

The only way to know exactly what is in an oil is to have it put through some tests. One commonly used test is the gas chromatograph. This is a complex, sophisticated machine that can take a drop of essential oil (or many other compounds, for that matter) and break it down to tell you exactly what is in the oil, and how much of it. For example, in a typical sample of lavender oil, there can be up to 100 different chemicals, but, probably only about 20-30 "main" components. And of these 25 or so, the 2 present in the greatest quantity should be linalol, an alcohol, and linalyl acetate, an ester. These 2 compounds are often the ingredients that give lavender its great disinfectant (the alcohol) and sedative (the ester) qualities.

Of course, if you don't have access to these results, or, even if you do but do not know chemistry, and most casual purchasers of essential oils don't....how do you know whether or not  you have a good oil?

We'll leave that discussion for next time!!

No comments:

Post a Comment