Essential oils are produced from plants grown all over the world. Some oils are distilled in the country of origin, even at the field location where they are grown.
Other oils come from plants that are dried and shipped to large distillation centres in Europe for processing. The essential oil trade is a large one and the aromatherapy side is only very small, about 2% of the total. Some essential oil producing plants have a very low yield - jasmine for instance requires 8 million blossoms to produce one kilogram of oil. Taken together, all these factors mean that an individual aromatherapy supplies company has to be extremely careful about buying essential oils.
The opportunities for adulteration, or mixing compounds extracted from another, usually cheaper oil into a more expensive one, occur at every level of the trade. Pharmacists and companies in the food flavouring business - the two main users of essential oils - do not necessarily see this as a problem. They want an oil that is stable, always the same. Most people would not want their peppermint chewing gum to taste different to last years, just because a hot summer produced a more intense flavour oil. But what aromatherapists want is a pure oil which contains all the compounds found in the parent plant. They do not want it modified to smell sweeter or the same as last year's crop. So how do we make sure this does not happen?
Most reputable aromatherapy supply companies now make some claim that they prevent impure oils being passed off as the real thing. How successful other companies are we don't know, but at Bay House we have a rigorous policy to ensure that our oils are not just pure, but of excellent quality. Our quality policy has three aspects to it, all of which are important.
2. Scientific profile
3. Organoleptic characteristics - don't worry about the long word, we'll explain it below!
1. Sourcing an oil is always important and here at Bay House we choose our oils either from one of the few independent UK growers, or from a fellow member company of the Aromatherapy Trade Council. It is vital to trust your supplier, and the company which imports most of our oils for us is a small one just like us, run by an individual who spends much of his time checking on the crops and quality of the oils wherever they are harvested anywhere in the world. Many of the importers who sell to aromatherapy supply companies are large multinational companies who do not really understand the specific requirements of aromatherapy. We feel our suppliers do understand the specific needs of
aromatherapists, just as we do ourselves here at Bay House - you want pure oils of the best quality, unmodified and with full botanical and scientific data available.
2. This botanical and scientific data includes the country of origin where the plant was grown, its Latin name and the part of the plant from which the oil was extracted, the method used - was it by steam or water distillation, cold pressing or solvent extraction? When we bottle up an oil we always write on the label not only the Latin or botanical name but also the best before date that the oil should be used, and a batch number which allows us to trace each bottle back to its source.
We need to know the physical characteristics of the oil. An oil is measured for its specific gravity, its refractive index, and optical rotation. Specific gravity compares the density of an oil against water - Lavender oil for instance may show a reading anywhere between 0.883 and 0.895. The refractive index of an essential oil is dependent on the apparent ability of liquids to "bend" a straight line. If you look at a straight line as it goes through water, it appears to bend at an angle of about 60° to the horizontal. This optical effect is called refraction, and the refractive effect of any substance can be measured - this is called the refractive index. The refractive index for Lavender oil is between 1.459 and 1.464. A reading outside the normal limits will indicate that there is something wrong with the oil - it may have been modified or it may be old and have started to
In optical rotation a beam of plane-polarized light of the same wavelength as sodium is passed through a horizontal glass tube containing the essential oil. Water produces a zero effect but essential oils will either rotate the light to the left or the right. Adulterants will modify the result and it is this that a skilled observer will look out for.
As well as the physical characteristics of an oil, we need to know the chemical nature of it. Does it contain the right constituents? A rose oil should contain over eighty constituents, some of them in tiny trace amounts. Other oils may differ in character, depending where in the world they are grown. We need to know, for instance, that high-camphor lavender from Bulgaria is not being passed off as best high-altitude French material. The method most commonly used today is Gas Liquid Chromatography
(GLC). Put at its simplest, this involves passing the oil to be analysed through a column with the help of a carrier gas such as helium. The speed at which the various compounds vaporise is measured and illustrated on a graph called a chromatogram as a series of peaks.
It is essential for anyone who is interested in the constituents of an oil to have a GLC analysis. If there is a concern that any of the constituents may have been added not by nature but by a dishonest trader, we also use Mass Spectrometry
(GCMS), which provides an analysis of the molecular structure of the individual constituents of an oil.
3. The organoleptic characteristics of an oil may sound very technical, but all it means is using our senses to evaluate the appearance, colour and odour of the oil. Just because an oil has passed all the scientific tests doesn't mean that we (or you) will like it. A cloudy oil may indicate that it is old, as may a thicker oil than usual. But apart from any imperfections in the oil, not all essential oils with the same name smell the same. Oils are produced in many countries, should we buy a Clary sage oil from France or from Hungary, a Bergamot oil from West Africa or Sicily? Only someone who has developed a "nose" from many years in the business will be able to appreciate the difference. In fact it always surprises us, how many people prefer a bland oil, rather than one with a rich top note. Perhaps so many years of being familiar with only modified or sub-standard oils has dulled their palate. But we continue to seek out not only the pure, but also those oils with the fullest aromas. Try our oils
and we think you will be pleasantly surprised.
Our ethical policy at Bay house has three prongs, concerning animals, plants and people.
Nearly all essential oils have been tested on animals at some time in the past. This was by companies using the oils for food flavouring and toiletry manufacture. We operate a fixed cut-off date policy and will not sell any products which contain any ingredients tested on animals after 1978. In practice most of the ingredients apart from the essential oils have been quite recently formulated and have not been tested on animals at all.
Most essential oils are grown from plants sown and harvested for that purpose. Where they are taken from the wild, we insist that no plant is taken from a source that is not sustainable.
Wherever possible we buy from small farms and co-operatives where the profits go directly to the producers. Our importer feels very strongly about this and was personally involved in setting up a fresh water scheme in Somalia to benefit the frankincense gatherers. We do not buy oils produced from crops which have been harvested in conditions involving the exploitation of children.