C02 Extracts: Part 1
CO2 Extraction: Part 1
During the past few months many people have subscribed to the newsletter. In light of that I would like to mention that they(the newsletters) take on several forms.
1. Newsletters on a specific aromatic plant and its essence or a specific topic related to the subject. Recent newsletters in this category that I have not yet been posted on the web site are on White Rose Absolute, Lemon Tea Tree, Ambrette Seed, Sweet Marjoram, Distillation Techniques, and Direct Sourcing of Essential Oils(Sources and Tips on how to make it all work.) If you would like me to send any of the above kindly inform me.(please specify which ones)
2. General newsletters which cover a variety of topics
3. Newsletters which inform customers that they can join with me on an order for specific essential oils, CO2 extracts, etc. This ends up saving everyone a nice amount of money as well as gives access to a wider palette of oils than I myself can offer A special feature for those of you exploring the world of Natural Perfumery starts with this newsletter.
As mentioned before, Mandy Aftel, author of Alchemy and Essence, has kindly consented to offer her insightful comments on selected absolutes, essential oils, CO2 extracts. This first essence she is taking up is White Rose Absolute. Kindly note that Mandy has also started an online Artisian Perfumers Discussion Group. You can join it by contacting her at-
White Rose Absolute
White rose absolute is exceptionally sweet and smooth with great clarity, subtlety and beauty. This light rose possesses less depth and tenacity than a red rose and in a perfume, will not hold its own against more intense middle and base notes. The perfumer should take care to preserve its exceptional qualities of complicated rosiness combined with a lightness and lift -- the capacity of middle notes in a perfume note being perceptible in the top note --- that is unusual in rose.
Many of you are either familiar or becoming familiar with the CO2 total and select extracts of various botanicals, aromatic and otherwise. The terms total and select as applied to Supercritical CO2 extracts need a simple explanation so that the two different materials are not confused(as the prices on the specified extracts also vary considerably). First the Supercritical process extraction technique uses slightly warmed(31 degrees Centigrade) Carbon dixoide to extract the aromatic constitutents of a plant(for Select Extracts) and the aromatic constituents plus the lipophylic consituents(for total extracts) In both cases the properly ground or pulverized material is placed in a pressurized chamber into which the Carbon dioxide is pumped. The Carbon dioxide in this presurrized condition remains in its gaseous state but displays the quality of a liquid and effectively dissolves the targeted constitutents of the plant. Lower pressure conditions remove the volatile oils(Select extracts) and higher pressures(Total extract) remove the fatty oils, waxes, pigments, etc that naturally exist in the plant.
A Select Extract is therefore much like an essential oil whereas a Total Extract is much like an oleoresin or a concrete depending on the type of material being extracted. Total extracts can have the consistency of a flowable liquid, a butter or a waxy solid concrete. The main advantages of the CO2 technique from the Select Extract point of view is that the volatile oil produced is done so with comparatively little thermal degradation(because of very little heat used in the process). In steam or hydrodistillation the higher temperatures can result in some compositional changes of the aromatic consitutents(which in some cases actually make the oil more beautiful but can also have negative results) .
It is said that the odor of the CO2 Select Extracts are closer to the material as it exists in nature. But due to the fact that most consumers are use to the odor of the steam or hydrodistilled essential oil, it is also possible that they may find the CO2 Select Extract-different than what they have normally encountered. Like any new essence that we explore one has to devote a lot of time to studying them in all phases from topnote to dryout to understand what the character of that oil is. For each and every oil is a complex being that displays many unique facets of their personalities only when one has cultivated an acquaintance with them. The main advantages from the vantage point of Total Extracts is that the lipophylic constitutents that normally are extracted with a potent chemical solvent like hexane and which can leave residues in the final product(albeit very small) are not present as CO2 readily evaporates out of remaining extract when processing is done. Indeed as the majority of CO2 extracts are used in food products this is an important consideration. It also means that both volatile constitents and lipophylic constituents can be extracted in one operation. If only the volatile constituents are desired then the procedure can be stopped after they are removed(as they are the first to come out) or if the total extract is desired then the processing can continue under higher pressure until the lipophylic constituents are obtained. The down side is that this type of equipment is very expensive and requires a highly trained staff to keep in good running order.
This is a very simplified version of what takes place in CO2 extraction and in order to understand the intricasies of the process one can go onto a search engine like Google and simply type in the term Super Critical Extraction, Super Critical Extraction Essential Oils, or even Super Critical Extraction Chamomile(or any other plant that they wish to know about for which a CO2 extract is available) A wealth of information can be accessed in this way.
Now having mentioned all these things I would like to very clearly state that I feel that CO2 extraction is just one more method of extracting or distilling miraculous constituents of plants. The other methods of steam distillation, hydrodistillation, etc also can produce incredible and beautiful results. It all depends upon the beauty of the raw materials, the people engaged in caring for the plants, the people distilling or extracting them, etc. What CO2 extraction offers us is another dimension of the world of aromatic essences. It is a fine addition to the palette of materials that people require for creating their own natural aromatic products be they perfumes, cosmetics, massage oils, incense, room refreshners and a multitude of other simple pleasures that bring charm and delight to our lives. People entering the world of CO2 extracts therefore need to define their own end product use in choosing to buy a Select or Total Extract. As Select Extract is naturally going to have the aromatic bouquet of the extracted plant. The Total Extract is often going to have a much reduced olfactory impact but is going to contain the equally precious fatty oils, waxes, pigments, etc that undoubtedly play an important role in the overall healing virtue of the plant.
I mention all the above things as I am now going to start offering a chance to participate in preordering of CO2 extracts both select and total. Many of them I do not personally stock. As you will see the prices of the CO2 extracts can be more expensive than the corresponding essential oils, fixed/carrier oils, etc. but by participating in preordering I think the price for many of them will come in the range of affordability. Please note that their are 8 ounce minimums on all the listed CO2 extracts. If you wish to procure in 16 ounce quantities there is a 10% discount over 8 ounce price. There is a 20% discount over the 8 ounce price for 32 ounces. I am only going to list the 8 ounce prices to conserve space in the newsletter so you will need to do the math on larger amounts. I will be placing the order for the CO2 extracts next Wednesday February 20th so I will need to have your order by Tuesday February 19th. Please note and this is very important-you should have experience or knowledge of the materials you are ordering. If not you should have the daring to order the materials and be content when they arrive on your doorstep. There are absolutely no returns of the CO2 extracts once you have informed me of your needs and I have ordered them. Also kindly have your funds in hand so that when the consignment arrives you can send me the money immediately as I need to pay the extractor ASAP. I plan to make an order for CO2 extracts every 4 months so this is not the only time during the year that you will have the opportunity to order.
Some web sites on Supercritical CO2 extraction
very good article on CO2 Total Extracts
basics of supercritical extraction and plant set up
diagrams of extraction units