What Is an Essential Oil?

An essential oil is the very soul of an aromatic plant. It’s the volatile essence extracted from aromatic plants through a process called distillation. This complex substance contains aromatic molecules whose health benefits are studied and applied in aromatherapy.

Essential oils are typically obtained by steam distillation. Despite what the name suggests, a pure and natural essential oil contains no fat or oil. During distillation, steam passes through the plant material in a still. The heat bursts the cells containing the essential oil, and the steam carrying the oil is then cooled in a condenser. The oil is then separated from the water.

For citrus fruits (like lemons or oranges), essential oils are often extracted through cold pressing of the peels and zests, a much simpler method when the oil content is high.

Essential oils are costly because their extraction involves delicate and labor-intensive processes.

Some striking figures:

To obtain just one liter of essential oil:

• It takes 4 tons of petals of Damask rose

• It takes 150 kg of flowering tops of true lavender

Each essential oil contains numerous active components. For example, phenols are powerful actives found in many plants such as Ceylon cinnamon, bay St. Thomas, clove, and thyme (thymol chemotype). These components determine the therapeutic effect—it is the molecule that heals, not just the plant that carries it. Phenols are known for their anti-infectious properties and are thus essential in treating many illnesses. The choice of component is key to ensuring treatment efficacy.