Chances are you’re all well aware of what essential oils are and maybe you’re big fans (like us) and with good reason! They’re amazing when it comes to all natural skincare and they can do wonders for your mood and overall mental wellness, but are you familiar with how essential oils are made? We think it’s quite an interesting process so in this week's Deep Dive we dove deep (like really deep) into the fragrant world of essential oils—because surprisingly there’s more to them that meets the eye! We started off with the basics (as well as the not-so-basics) so keep scrolling and get ready to become an essential oil pro.
What Is An Essential Oil?:
First things first—what exactly is an essential oil? An essential oil “is a concentrated hydrophobic liquid containing aroma compounds from plants.” Sounds fancy, we know. There are also tons of essential oils to choose from that come from a variety of different plants which are typically used in either aromatherapy, alternative medicine (with caution) or natural skincare.
You may have noticed when shopping for essential oils various small brown bottles labeled as “essential oil”; however, not all essential oils at the store is considered true essential oils. Confused? Let us explain. For example, many people will call absolutes and CO2 extractions essential oils, but technically that isn’t the case even though they are very similar. In order for a substance to be a true essential oil, the oil must be extracted through “distillation with either water, steam or by mechanical processing.”* Absolutes and CO2 extractions are extracted in a different way (which we’ll explain later) and even though they still work wonders, and have a multitude of uses they’re just technically not essential oils.
How Are They Made?
The methods of extraction are fairly simple. For starters, there are two types of extracting methods. One process is called distillation which uses steam to extract the essential oil and produces hydrosols as a byproduct. The second is called expressions which are only used to produce citrus oils. We’ll be focusing more on the distillation process since it’s the most common out of the two.
STEP 1: Before the distillation process begins, some plants must be prepped (such as crushed/opened) before starting so the steam can get through because the most potent essences are sometimes stored deeper within a plant.*
STEP 2: After the plant is prepped, the distillation process begins. Now, there are a few different types of distillation process’ explained below.
Water Distillation: This is when the plant comes into direct contact with the water and is usually used with more delicate plants, such as flowers.*
Water and Steam Distillation: This is when the plant is placed on a grate above water while the steam is introduced from the outside and the essential oil is extracted through the indirect steam.*
Steam Distillation: This is the most common method and it’s when steam is injected into a large chamber with the plant, usually at a slightly higher pressure and temperature, in order to extract the essential oil.*
STEP 3: The essential oil is then captured in the steam which then rises into another chamber called the condenser which cools the steam and oil vapors. That then travels into another chamber called the separator which separates the oil from the water byproduct, also known as hydrosol—and ta-dah you got yourself some essential oil!*
Other Methods of Extraction
A few other methods of extraction include enfleurage; which produces absolutes, solvent extraction; which produces absolutes and resins, and CO2 extraction; which produces CO2 extracts.
Enfleurage: This method is usually used for flowers and focuses on a cold-fat extraction process that is based on the principle that fat is highly capable of absorption. The final product is known as an enfleurage, or an absolute and has a very potent aroma.*
Solvent Extraction: This form of extraction creates an absolute and is typically used on very fragile plants. This method will use a solvent extraction as the solvent, such as petroleum ether, methanol, ethanol or hexane which extracts the lipophilic (aka fat or in this case, essential oil) material from the plant. Most of the solvent is no longer present in the finished product, although there can be trace amounts of leftover that are considered generally safe for all uses.*
CO2 Supercritical Extraction: This form of extraction makes a CO2 extraction. This method is relatively new and is based on the concept that CO2, when under enough pressure, will turn into a liquid that can then be used as an inert liquid solvent. The liquid solvent is then able to extract its aromatic constituents of the plant, thus extracting the essential oil.* We talked a little more in-depth about this in our Deep Dive on rosehip oil, which you can read here.
How To Use Essential Oil
Essential oils can be super potent so it’s advised to not use them alone directly on your skin and to dilute them with a carrier oil such as jojoba oil, grapeseed oil, avocado oil or whichever oil best suits your skin type. If you have more sensitive skin, but still want to reap the benefits of essential oils, you can use the byproduct also known as hydrosol. Hydrosols have many of the same benefits as essential oils (and some additional) but are much more gentle on the skin. They make a great alternative for use on super sensitive skin, children, and the elderly. But more on that later...
For a more in-depth guide on essential oils (such as best uses as well as our favorites) keep your eyes peeled for future posts here on The Supercritical!
*NY Institute of Aromatherapy: The Basics of Essential Oils