How To Make Essential Oils

There are several techniques used in making essential oils. These include hydro distillation, steam distillation, solvent extraction, CO2 extraction, cold press and florasol extraction.

With skill and practice and the right essential oils distillation equipment, you can use several of these methods at home.
Plants two types of oil. Aroma Therapy is interested in the essential oils that is almost always extracted from the non-seed part of a plant. Fixed oil is extracted from the seed of plants, and while these oils have many uses including sometimes being used as carrier oils, we won’t deal with them here.

Long before writing had been invented, essential oils were being extracted from plants and flowers. Distillation pots have been found that can be dated to 3500 years in the past. Of course, the earliest method of distillation bore little resemblance to modern methods of distillation of Essential Oils.

Distillation of Essential Oils

Sometimes when people think of an aromatherapy distiller, they will picture the stills that ‘moon-shiners’ used. And to some extent they will be correct. There are a lot of different types of stills, but the process is essentially the same.

The earliest form of distillation used in making essential oils is what we today call hydro-distillation. The plants, flowers, wood or roots are placed in a pot and covered with water. This created what could best be described as an essential oil soup. This would be boiled down but would lose some of the essence and was diluted in effect. Eventually steam distillers of essential oils were invented to derive a purer result.

Steam Distiller Essential Oils:

The steam distillers of essential oils are another type of aromatherapy distiller.
The first steam distillers of essential oils were developed in Egypt. This process used multiple chambers. The steam was heated in one chamber and forced through a second chamber where the plants, flowers, shrubs, trees or roots had been placed. The steam heated the foliage to a high temperature and as the essential oil was released it attached itself to the steam. The steam was them bled off into a third chamber where it was cooled. As the steam cooled, it returned to its liquid state, water. As we all know oil and water do not mix so the essential oil rose to the top of the now distilled water. The oil was then skimmed off the top.

Solvent Extraction:

Solvent extraction is another method used for distillation of essential oils from very delicate flower petals like jasmine and rose and linden blossoms. The petals of the flowers are placed on trays that have tiny holes in their bottoms. The petals are submerged and re-submerged into a solvent. The solvent most often used today is hexane.

The solvent actually dissolves all the material in the petals that can be dissolved. The wax, pigment and, of course, the essential oil are all dissolved. The solvent which now contains all of the dissolvable material that has been extracted from the flower petals goes through a low-pressure distillation process. The solvent is separated from the plant material and used again and again. What is left is what is called ‘concrete’.

The concrete is a waxy substance so the next step is to separate the wax from the essential oil. Essential oil is referred to as the ‘absolute’. To achieve this separation, the waxy substance is heated and ethanol alcohol is stirred into the mixture. The absolute or essential oil are soluble in the alcohol but the waxy substance is not to the separation takes place. It is not, however, a complete separation. Some of the waxy substance will still be contained in the absolute.

The next step to affect a pure essential oil is the freezing process. The waxy substance will freeze but the essential oil will not. The mixture is agitated and then frozen at an extremely low temperature…usually at about MINUS 30 degrees Fahrenheit. The freezing process takes out almost all of the waxy substance but still not quite all of it. There is a final step of cold filtering that is accomplished in order to produce the absolutely pure absolute (essential oil).

CO2 Extraction:

Another process to make essential oils is by the use of carbon dioxide (CO2). The CO2 process has also provided the world with some essences from aromatics that do not yield essential oil like rose hip seed and calendula.

The CO2 extraction process is very much like the solvent extraction process. The general principle is the same. However, the CO2 process does not require separation steps. The CO2 is normally a gas. It only becomes a liquid when it is put under very high pressure.

During the CO2 extraction process, the CO2 is put under high pressure, it becomes a liquid, it is circulated through the perforated trays containing flower petals or other foliage. When the pressure returns to normal, the CO2 returns to its normal gaseous state and all that is left is what is referred to as the ‘total’. There is no solvent residue as there is with the solvent extraction process. This is a mixture of the waxes, resins, pigments and, of course, essential oils or absolutes.

Separating the essential oil or absolute from the other things that are contained in the total is accomplished in the same method as that used for solvent extraction.

The best thing about the CO2 extraction method of Making Essential Oils
is that the total extraction is just about as close as you can get to the essence of the plant itself with the possible exception of Florasols which we will discuss shortly.

*Note: With distillation, steam distillation extraction process, the solvent extraction process and the CO2 solvent extraction process there will always be variations in consistency. No matter which essential oils distillation process is used there will always be variations in output. This is because plants do not come off of assembly lines. There are always variations in nature. Some plants will contain more essential oils while other plants will contain less.

Cold Press Extraction:

The cold press extraction process is mainly used for Making Essential Oils
from citrus fruits. The cold press extraction process produces a more concentrated essential oil than does the steam extraction process.

The fruit is rolled down a trough that has many small spikes embedded. The skin of the fruit is pricked by the spikes. The essential oil in citrus fruit is contained in the skin of the fruit and not in the fruit itself.

Once the skin has been pricked, the whole fruit is crushed. After its crushed, the oil rises to the top and it is skimmed off.

Florasols Extraction:

This is a relatively new essential oil extraction process.

Florasol (R134a) was developed as a replacement for Freon as a refrigerant. Florasol is a benign non-CFC gaseous solvent. It is an ozone friendly product and it poses no danger to the environment.

One advantage is that the extraction of essential oils occurs at or below room temperature so any degradation through temperature extremes does not occur.

The only thing that is extracted from the plants are the essential oils. The essential oils are absolutely pure and contain no foreign substances at all.

At the present, there is only one company using this process but you can be pretty sure that others will be following in the near future.

Extracting the essential oils from plants, flowers, trees and shrubs has always been the first and most difficult step. The value of the essential oils to human kind has never been in dispute. However, there has always been and likely always will be a debate over the best process by which to extract the oils.