Archive Newsletter 4 Meet the Linas June 2012
the Winter Solstice and Matarkiki (Maori New Year) in New Zealand just passed but for us the worse of our winter is to come. My emerging fragrant garden is holding up well to the frosty onslaught with the help of frost cloth. The osmanthis hedge seems settled and happy in its sunny and sheltered spot (we get a fierce cross wind here). This newsletter is about some oils which I like referring to as 'The Lina's"- Rosalina and Nerolina. These are two wonderful oils native to Australia and gentle cousins of teatree. The other issue I would like to touch on is essential oil quality which I get asked a lot about. A really easy way to think of this is to equate essential oils to the wine industry- fine champagens from specialist suppliers right the way down to the wine on the bottom shelf of the supermarket that you used to drink as a student. Firstly back to basics -an essential oil is"
“…a product made by distillation with either water or steam or by mechanical processing of citrus rinds or by dry distillation of natural materials such as roots, bark, leaves, twigs, flowers or berries. Following the distillation, the essential is physically separated from the water phase” (ISO/DIS 9235) . However you need to keep in mind the myriad of other genuine aromatic materials such as absolutes, resins, CO2 extracted oils, phytols amongst others. This does not mean that these substances are any less pure or are inferior to essential oils, just that their process of extraction is different. Over 90 % of world essential oil production is not for therapeutic use -quantity is more important than quality Synthetic and nature identical oils- these are not natural and as long as they are labelled as such there is no issue for the purist.’
Why does adulteration occur?
As mentioned earlier essential oil production is big business. Oils which are difficult to produce cost more. Other factors also influence crops such as a poor climate, political instability or harvest failures. Incredibly there are many different ways oils can be adulterated to deceive you the consumer. These include:
- Deliberate mislabelling-supplying a cheaper grade of oil than what label implies or saying an oil is from one country
- Modification by various means e.g. redistilling to remove undesirable compounds or fractions (e.g. eucalyptus or fennel oil);
- Cutting expensive oil with cheaper oil (e.g. Melissa with lemongrass);
- Diluting or stretching the oil in a carrier oil or alcohol without labelling as such. .
How can the consumer be sure of quality? Producers may have various documents to support their oils and these may make it to the end retailer. Quality tests include include a GLC, specific gravity (SG)-every oil has a reference SG which can be used to detect adulteration by dilution or addition of solids; refractive index (RI) - most oils have a RI reference range.For more accurate analysis MS (mass spectrometry) and IR (infra red) techniques are used which further break down constituents into individual electrons. Other techniques use enantiomeric columns which show up different isomersThere are a number of sophisticated ways of detecting adulteration of essential oils. However these all cost and may not be done on each batch- so for you as the end producer there are a number of basic check s to make if you aren't lucky enough to e buying 'off the farm'. As a minimum, pure essential oils should be labelled as such, there should be a common name, a botanical name and a country of origin identified. There should also be a batch number or expiry date or date of production. If the oil does not meet all of these reject it outright as it is probably adulterated in some way. Next oils should be packaged in dark glass bottles to protect the oil from degradation. If you can, smell the oil- it is best to not sniff straight from the bottle-rather sniff the lid or place a drop on a piece of paper. Even if you are not sure of the true smell of the oil it should smell similar to the fresh plant in most cases. Of course there are variations to this rule. It does take time to train your nose. If a seller does not have testers from the same batch as what is for sale then you also can’t be sure exactly what you are buying. The next thing is to look at the colour of the oil-most will have some colour but some oils do have a distinctive colour. For example German chamomile and some yarrow oils are bright blue and as they age they go green then brown. Patchouli oil can either be light or dark depending on the source. Another simple test is to place a drop of oil on blotting paper or similar. Genuine essential oils will evaporate completely after a short period of time. Those adulterated with fixed carrier oils will leave a greasy trace on the paper. Some oils though are naturally heavily pigmented and will leave a stain. Finally you can run a drop of oil through your fingers-it should feel mobile and not greasy. The best ways as a consumer is to trust your supplier and use the labelling as your guide. Price also gives an indication of quality. Oils vary enormously in price- starting at less than $1 per ml retail for some citrus oils to over $20 per ml for rare and precious ones like rose, German chamomile and Melissa. Certified organic oils are generally about 30-100% dearer than non-organic. At the end of the day it really depends what you want to do with your oils-if they are just going in the burner to get rid of a musty smell in the house then why would you use top quality organic oil. Oils can be likened to wine- very few of us get to drink Bollinger every day and can cope with chateau supermarket brand of wine. We save the Bollinger and others of that price for the very special occasions! Likewise the best quality oils are used for when it really counts and you need a therapeutic effect more than just something smelling pleasant.
As a minimum check the label and price list from your supplier. The following information should be readily available when purchasing a quality essential oil.
- Botanical name.
- Part of the plant used (some plants have oils from different parts and this can affect both quality as well as action).
- Country of origin.
- Extraction methods used.
- Chemotype/variety if necessary-e.g. thyme has several different chemotypes as does rosemary and niaouli oil.
- Expiry date or date of production. Generally oils last for up to 2 years from date of distillation. Some such as frankincense and patchouli improve with age, whereas Teatree and citrus oils can go off very quickly. Some producers may also supply monographs of their oils. These include all of the information already discussed as well as details about the habitat of the plants, therapeutic actions, historical or traditional uses if known.
Don't forget the greatest Aromatic Event of 2012 is Botanica2012 in Dublin- have you booked yet?? It will be a wonderful time to connect and learn and share with all sorts of people from around the world. I am getting so excited about being of this event and love reading the bio's Rhiannon is putting up on face book. Now let us explore our friends the Lina's in more detail- these 2 wonderful oils are the soft and gentle cousins of tea tree (well soft and gentle in appearance and aroma) but they certainly pack a powerful therapeutic punch in their own right-I like them both so much and find it hard to pick a favourite bit if I HAD to then I would edge towards the rosalina... what about you? Do you have a favourite?
On a different note I am trying to source samples of NZ manuka and kanuka grown in different locations around the country to distill in my own lab to bring with me to Botanica2012. I put a request over a chatroom messageboard in the vague hope I would get a response and it has been amazing how kind people have offered to harvest a small amount for me off their properties.
Posted: Tuesday 4 January 2022