Essential Plant Oils: Exploring the Extraction Methods Used Today

There are a number of benefits believed to be attached to natural oils and it offers a natural way to heal yourself amongst other things, but how are these oils extracted?

Great advances have been made in creating safe and reliable CO2 extraction systems, and you can get for example, which is much the same procedure utilized in the extraction of essential oils.

Essential Plant Oils: Exploring the Extraction Methods Used Today

CO2 extracts explained

Oils that are extracted by using the carbon dioxide method (CO2) are often referred to as CO2 extracts or you might find this method description shortened and simply referred to as just CO2’s.

Carbon dioxide is a gas that are continually breathing in order to sustain life and we do this while it is in its normal state. It is possible however, to pressurize this carbon dioxide until it is transformed into a liquid.

Once in this state, the liquid carbon dioxide can then be used to work as a solvent, giving it the capability to be able to dissolve the natural elements found botanical materials, when it is exposed to this liquefied CO2.

Essential Plant Oils: Exploring the Extraction Methods Used Today

Natural pressurization

The next step in the process is to bring the CO2 back to its natural state of pressurization, allowing the carbon dioxide to then revert back to its normal gaseous state, leaving you with the extract desired.

Essential Plant Oils: Exploring the Extraction Methods Used Today


If you go back in history and trace the origins of the extraction processes used, you will see that some methods have been in use since ancient times, with a technique like enfleurage evolving from these initial experimental beginnings.

Modern methods of solvent extraction like enfleurage have been around for many years before CO2’s became an established part of the current extraction ways that are routinely deployed today.

This is a cold-fat extraction process, working on the principle that fat contains a higher level of absorption, which is certainly the case when it comes to animal fat for example. Enfleurage is widely considered to be one of the most expensive methods of extraction, which is why it is not widely used today in most commercial operations, simply due to the fact that it would prove to be too cost-prohibitive for consumers.

Essential Plant Oils: Exploring the Extraction Methods Used Today

Hypercritical extraction – in layman’s terms

In comparison to other extraction techniques, hypercritical carbon dioxide extraction (CO2) is definitely the new kid on the block, but it is understandably popular when producing aromatic products.

To put the process in layman’s terms, the basics are that CO2 when it is put under sufficient pressure, will be changed from a gas into a liquid, allowing it to then be used as an inert liquid solvent.

This liquid solvent is subsequently able to diffuse throughout the selected plant material so that it can successfully extract most of its aromatic properties. What you will find is that carbon dioxide extracts are largely made up of the same ingredients as you would find in essential oils, but the fundamental difference is that they also contain some elements that you won’t find in essential oils.

Essential Plant Oils: Exploring the Extraction Methods Used Today

Several advantages

The fact that that CO2 extracts contain additional properties can be perceived to be an advantage in certain production scenarios.

One example would be the fact that the CO2 extract of contains immune-enhancing and anti-inflammatory properties which are not present in the essential oil equivalent.

It should also be said that CO2 extracts have also gained a good reputation for their ability to produce an aroma that is able to closely match the original plant aroma, even after the process has been completed.

Essential Plant Oils: Exploring the Extraction Methods Used Today

Low pressure CO2

In order to create a CO2 select, a certain degree of low pressure is required in order to liquefy the carbon dioxide.

What you will find is that CO2 selects invariably contain the aromatic elements of the chosen botanical that are then soluble in a liquefied soluble state. Some aromatic molecules are simply too weighty to be present in a steam-distilled essential oil, which is one example where CO2 selects are able to be used, as they are able to accommodate some of these heavier aromatic molecules.

The result of this benefit achieved through a low-pressure CO2 extraction method is that these so-called CO2 Selects are often able to closely mimic the original aroma of the natural plant being used, than you can often achieve via steam-distilled essential oils.

Extraction methods have definitely evolved over the years and there is now every opportunity to benefit and enjoy the results of these advanced techniques.

About the Author
Peter Roberts has studied herbal treatments and takes an interest in all forms of natural medicine. He blogs about using essential oils for health benefits, homeopathy and much more.


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