How Are Essential Oils Made?

Essential oils are compounds that are extracted from plants. They are often obtained through a process known as distillation (via steam and/or water) or mechanical methods like cold pressing. We will take a closer look at each of these methods below.

Steam Distillation

This is considered one of the more common methods of producing essential oils. During this process, steam is passed through a large hopper. This hopper is very similar to the steamer basket you may already use in your kitchen.

The hopper contains the raw plant material, and when the steam passes through, the plants begin to release their aromatic compounds. Those compounds then vaporize and rise with the steam and enter a closed cooling system that is located above the steam chamber.

As the plant vapor and steam then cool in a condenser chamber, the vapor turns back into a liquid and is then sent to the separator where the water is split from the oil. The water contains the plant’s essence and is often referred to as floral water. The oil soluble part rises to the top of this water in a separate layer. This is the essential oil portion of the plant.

CO2 Extraction

Another way to make essential oils is through CO2 extraction. During this process, pressurized carbon dioxide is pumped into a chamber that has been filled with plant matter. When the carbon dioxide is under pressure, it becomes supercritical and has liquid properties, even as it stays in a gaseous state.

Essential oils are obtained with relatively low CO2 pressure and have no temperature degradation. The consistency of the oils with this process may vary from batch to batch in much the same way that the plants will vary.

Expression

This method is used with citrus oils and is also known as cold pressing because it is a temperature-controlled process. The peels of the citrus fruit are poked and pricked so as to puncture the cells that contain the oils. The peels are then soaked in warm water and mechanically pressed. The liquid and the pulp are centrifuged after being pressed and are separated into a citrus juice and the essential oil.

Enfleurage

This process was used long ago so as to capture the essence of the more delicate flowers like jasmine and orange blossom. The flowers were combined with animal fat and then pressed between two pieces of glass. After a few days, the flowers would be removed and then replaced with fresh flowers, and the process was repeated several times over.

While this technique isn’t used as much these days, concretes and absolutes have begun to take its place because more and more people are saying no to using anything that is animal-derived.

As you can see, there are many methods used to make essential oils; however, steam distillation and cold pressing are two of the most commonly used methods and are the two methods that are still used today.

Meta: Essential oils are made through different processes. The two most common methods of making essential oils are through steam distillation and cold pressing.