The Art Of Fragrance Oils: A Creative Process

Fragrance oils are made through a variety of methods, both natural and synthetic. Natural fragrance oils are made by extracting the essential oils from plants, herbs, and flowers. This can be done by boiling the plant in water, soaking the plant material in alcohol or carrier oil, or through steam distillation. Synthetic fragrance oils, on the other hand, are created in a lab by perfumers using a variety of chemical compounds. These compounds can include carrier bases, alcohols, aldehydes, esters, and other synthetic chemicals. Synthetic fragrance oils are often less expensive, more consistent in odor and colour, and widely available compared to their natural counterparts.

Extraction of natural oils from plants

The first step in creating fragrance oils is to extract natural oils from plants or trees. There are several methods to do this, and humans have been refining these methods for thousands of years.

One of the most common extraction methods is steam distillation. This involves adding boiling water to the base of a copper or metal distiller, then adding raw plant materials to the cylinder. The oil-infused steam is then captured in a container filled with cold water. When the steam condenses back into a liquid, it will have separated into oil and plant-infused purified water, or hydrosol. Steam distillation is the most common extraction technique for essential oils, but it is not suitable for all plants, as some compounds decompose at steam temperatures.

Another method is hydro distillation, where the plant matter is boiled in water as a tea, and the steam is collected, cooled, and condensed back into a liquid, with the oil floating at the top.

Solvent extraction involves placing plant materials in a solvent such as hexane or ethanol. The plant is then soaked for a period of time to release the oils. This method is best for plants that do not normally produce large amounts of oil or cannot withstand more pressurized processes. The resulting mixture is filtered and vacuum distilled to remove the solvent, although trace amounts may remain in the final product.

Cold-pressing is a traditional method that is used for oils that degrade when exposed to heat, such as citrus fruits. This involves puncturing the rind of the fruit and using centrifugal force to move the oil away from the pulp. The oil is then collected in a container.

Finally, supercritical and subcritical carbon dioxide (CO2) extraction is an advanced method that is useful for the growing hemp industry. Carbon dioxide is subjected to specific temperature and pressure conditions to achieve different effects. It can be used as a highly "tunable" solvent, with variables adjusted to effectively extract targeted compounds while leaving others behind in the biomass.

Boiling plants in water

One of the methods of extracting fragrance oils from plants involves boiling flower petals in water. This is a simple but effective way of extracting oils from plant materials.

The boiling process is one of the oldest forms of oil extraction. It involves placing flower petals in water and heating the mixture to a boil. The oils are then released from the petals and can be collected. This method has been used for thousands of years and was commonly used by the Greeks and Romans.

Other Methods of Extraction

There are several other ways to extract oils from plants, including:

• Steam distillation: This method involves passing steam through the plant material, turning the essential oil into gas. The gas is then cooled and liquefied.
• Solvent extraction: Flowers are placed in large rotating tanks and covered with benzene or petroleum ether to extract the oils.
• Enfleurage: Flowers are spread out on grease-coated glass sheets and placed in tiers between wooden frames. The grease absorbs the fragrance over several weeks.
• Maceration: A similar process to enfleurage, but with warmed fats used to soak up the flower fragrance.
• Expression: The oldest and simplest method, involving pressing, squeezing, or compressing peels of citrus fruits to extract the oils.

The Benefits of Using Fragrance Oils

Fragrance oils are often created synthetically, which means they come in a broader range of scents and are usually more affordable than essential oils. They also tend to have a stronger and longer-lasting scent. Additionally, using fragrance oils can be more environmentally sustainable than using essential oils, as the production of certain essential oils, such as sandalwood oil, can be harmful to the environment.

Steam distillation

The steam distillation process was discovered in the 11th century by a Persian chemist named Ibn Sina. It is considered a gentle process that preserves the natural properties and aroma of the oils. This makes steam distillation popular for isolating essential oils, as it does not involve harsh chemicals. The steam acts as a carrier, lifting the aromatic molecules from the plant material. These volatile compounds then travel with the steam to a condensation chamber where they cool and return to a liquid state, separating from the water to form the essential oil.

The condensation step is crucial, as it allows the oil to separate from the water, resulting in a pure, concentrated essential oil. By controlling parameters such as temperature and pressure, the efficiency and quality of the distillation process can be optimised. Steam distillation is also versatile, as it can be applied to various plant materials, including flowers, leaves, roots, and bark.

However, steam distillation has some limitations. It may not be suitable for certain plant types, particularly delicate flowers or heat-sensitive plants, as the high temperatures can degrade the aromatic compounds. Additionally, some essential oil counterparts with higher boiling points may not effectively separate from the water vapour, leading to lower purity in the final product.

Overall, steam distillation is a preferred method for extracting essential oils due to its efficiency, gentleness, and ability to produce high-quality oils while retaining the natural properties and aroma of the plant.

Synthetic fragrance oils

The synthetic versions of fragrance oils are generally cheaper, more consistent in odor and colour, and widely available. They offer a greater variety of scents and utilize scent binders to help retain their aroma for longer. Synthetic fragrance oils are also more stable and have a longer-lasting aroma.

Natural fragrance oils

Essential oils contain tens of hundreds of individual molecules called isolates, which are single molecules. These isolates can be extracted from whole essential oils and natural raw materials like flowers, grasses, leaves, twigs, fruit peels, seeds, bark, and roots.

There are several methods of plant extraction. One can boil the plant in water, releasing fragrant oils into the water, and then let the water cool and separate out the oil. This method is a simplified form of distillation or solvent extraction if the plant material is soaked in alcohol or carrier oil. Another method is steam distillation using a copper or metal distiller. This involves adding boiling water to the base of the distiller, then adding raw materials to the cylinder and finally capturing the oil-infused steam in a container filled with cold water. When the steam condenses into liquid again, it will have separated into oil and plant-infused purified water, or hydrosol.

Frequently asked questions