Essential oils have a variety of uses, including cleaning, beauty, skincare, and aromatherapy, a form of alternative healing used for relaxation, stress relief, and restfulness. And while many people are fans of using essential oils for relaxation – many (if not most) don’t know how essential oils are made.
This article will explain the various methods of creating essential oils, the pros and cons of each process, as well as some of the oils that are created in each way.
What are essential oils?
But first, for those who have been living under a rock for a while, a quick explanation of essential oils.
Essential oils are solutions distilled from plants to create a concentrate with a higher potency than the original plant. The base of essential oil is the extraction of the aromatic essence of a plant. Each plant has a different reason in nature for needing these essences; some of these reasons include repelling predators, encouraging pollination, and protecting the plant from pestilence. Typically, they’re used for aromatherapy among other “Pinterest-inspired” things.
How Essential Oils Are Made
Because essential oils are not water-soluble (meaning that they can mix with fats, alcohol, and other oils, but not with water), the extraction methods must ensure that any resulting water that remains is removed after the oils are extracted. The method that works best varies significantly based upon the physical and chemical composition of the plant or source material.
Below is a detailed explanation of each of these various methods of creating these oils as well as their distinctive benefits and disadvantages.
The Methods Of Making Essential Oil Include:
Expression extraction is the most straightforward method of essential oil production and is achieved by pressing the oils from the skin, flesh, or seeds of a plant. This method is primarily used to extract oils from citrus fruits, such as grapefruit, lime, lemon, and orange, as the peels contain oils that are easily squeezed out. The skins of the plant are first pierced to puncture oil-containing cells; then the peels are pressed.
The resulting liquid and pulp are then spun in a centrifuge to separate the juice, pulp, and essential oils.
The majority of essential oil is manufactured from plants using a process known as steam distillation. Steam distillation is achieved through suspending fresh plant material (flowers, leaves, peels, seeds, bark, or roots) in a hopper, which is similar to a steamer basket in the kitchen over boiling water and allowing the steam to draw the oils and aromatic compounds out of the plant. When the steam rises, it is caught in a container and moved through tubes. The steam is then cooled quickly to cause it to return to its liquid form. As water and oil do not mix, a separation occurs, and the separated essential oil can be removed from the container. The quality of essential oil extracted by means of distillation depends largely on low temperature and low pressure during the process.
Another distillation method, called hydro-distillation, requires plants to be completely submerged in water. In the case of hydro-distillation, steam is forced in through the top of the container holding the plant rather than through the bottom. Many plants cannot endure such a high-temperature extraction method, so in those cases, traditional steam distillation would be preferable. The most common essential oil types (eucalyptus, tea tree oil, peppermint, lavender, and patchouli) are creating using this method.
Carbon Dioxide Extraction
Carbon Dioxide extraction is a newer, more expensive method of creating essential oil. As the name implies, oils produced from this method are extracted from their plant source using carbon dioxide. As Carbon Dioxide is a naturally occurring element, it helps maintain the bright scents of the plants from which the oils are being extracted. Although this method is gaining traction and popularity, it is still not used much in mainstream essential oil production. To extract essential oil using Carbon Dioxide, plants and Carbon Dioxide are placed into a chamber, which is then warmed slightly (to 85 degrees Fahrenheit) and put under extreme pressure.
The combination of the temperature and the pressure causes the Carbon Dioxide to enter a supercritical state, meaning the Carbon Dioxide is all at once part liquid and part gas, allowing the plant aromatics to dissolve into the Carbon Dioxide fog. The supercritical Carbon Dioxide is then separated from any remaining plant material, then returned to normal pressure. Once normal pressure is achieved, the Carbon Dioxide will return to its gaseous state, and the extracted aromatics are left behind.
Using solvents to create essential oil is a less popular method than the others mentioned previously, mainly because there is some concern that traces of solvents used might remain in the oil, creating a less pure product. To create essential oil using this method, plants are dissolved in a solvent (hexane, benzene, etc.), and the solvent is then removed by vacuum. Sometimes, paraffin wax is used as the solvent, but as the wax does not evaporate, the essential oil product is solid rather than liquid.
Enfleurage is an old method of creating essential oil that is mostly unused today except in French essential oil production. The process is a long, complicated one that requires several days, and as a result, has become increasingly expensive over the years. Enfleurage requires two items: flowers or plants and an odorless fat.
During Cold Enfleurage, a plate of glass is smeared with fat, and after the fat sets, flowers are placed on the fat, and the scents defuse over several days. The process is then repeated with a new batch of flowers until the fat reaches the degree of fragrance desired.
During Hot Enfleurage, the fat is heated, and the flowers are added to the fat and stirred well. Used flowers are strained from the fat regularly, and fresh flowers are added until the fat has reached the desired level of fragrance. In both hot and cold enfleurage, once the fat reaches the correct level of fragrance, it could then be soaked in alcohol to draw the fragrance into the alcohol, after which the alcohol is separated from the fat and evaporated, leaving only the essential oil behind.
It should always be kept in mind that although essential oils are created through natural means and natural processes, essential oil users should learn about and follow the rules of essential oil safety, as essential oil is very beneficial when used carefully, but improper usage can be harmful.
The various ways of making essential oils have evolved over the years, particularly with advances in technology to improve efficiency. If you, as an essential oil user, are uncomfortable with one of the extraction methods, be sure to read labels and inquire with manufacturers about the particular method that they use to achieve their results. This is particularly important when buying pre-blended essential oils.
Remember, knowledge is power!