Essential oils are the most straight-forward of the “aromatic group of materials”. They’re concentrated oils that are extracted from, well… aromatic plants. Some examples include rosemary, lavender, peppermint, thyme, etc. In the following, I’ll discuss in general terms how essential oils are extracted, and what methods are used for the extraction.
HOW ESSENTIAL OILS ARE EXTRACTED
There are several methods employed to extract the oils, the most common of which is steam distillation. In this method, raw plant material (flowers, green herbaceous parts, etc) is placed upon a grid (like a basket) in a still. Once inside, the still is sealed, and steam is passed through the basket, causing the plants to release their aromatic compounds (oils). These compounds then rise with the steam into a cooling apparatus, where the steam is cooled back into liquid form. As the liquid continues to cool, the water and oils separate.
The water contains the water-soluble (hydrophilic) parts of the plant material, which is why this remaining water is referred to as a hydrosol. Because oil and water don’t mix, the aromatic compounds rise to the top of the hydrosol, where they are decanted off, and then referred to as essential oil of that plant.
There are other other methods (which I will only briefly describe here) used to extract essential oils such as: 1) expression, also known as cold pressing, which is an extraction method specific to citrus oils, 2) hydro-diffusion – a relatively recent method very similar to steam distillation which is very useful for woody or “tough” plants such as fennel or dill, 3) water distillation – a method employed with flowers such as rose and orange blossoms, as direct steam causes these types of flowers to clump together making it difficult for the steam to pass through, and 4) solvent extraction, which is a method used for vanilla, and delicate flowers such as jasmine and gardenia.
HISTORY (AND A LITTLE RESEARCH) BEHIND THE USE OF ESSENTIAL OILS
It is well known that essential oils have been used for centuries in aromatherapy, skin care, perfumery and medicine. According to some interpretations, the extraction of essential oils for use in perfumery, cooking, and digestive aids appears to date back to roughly the 5th century and beyond. At present, one of the more well-researched essentials oils is lavender (Lavandula angustifolia). The health benefits of lavender are many, and there is sufficient evidence to support its use as an analgesic (pain-reliever), anti-inflammatory, topical antibiotic and antiviral, and mild anti-anxiety. A few other essential oils with increasingly documented efficacy include peppermint (Mentha piperita) – it has shown promise in relieving congestion and nausea, rosemary (Rosmarinus Officinalis) – to help relieve mild stress, muscle pain, and congestion, and Aloe vera – as a topical anti-inflammatory to help relieve symptoms associated with mild inflammatory skin conditions.
Well that covers, in simple terms, how essential oils are extracted, and how they have and are being used.
Apple Annie’s soaps are made with over two dozen essential oils, which account for a myriad of scented and aromatherapeutic combinations. Simply put, that’s another great reason to choose organic bar soap, a small change that will not only leave your skin beautifully conditioned and soothed, but also make you feel like you’re treating yourself to a tiny luxury every time you pick up a bar.
For more information, see our organic soap products page.