Essential oils are an indispensable component of aromatherapy, accompanying us during every session witha diffuseror as part of essential practices aimed at improving our well-being during stressful times. But have we ever wondered what actually lies within essential oils? What is their chemical composition, and what do they contain? Today we’ll take a look at these and other issues relating to the composition of essential oils.
Essential oils – why are they so remarkable?
Many plants produce essential oils to communicate with the outside world. These so-called volatile oils have an intense aroma and scent. Plants use them to mark their territory, attract pollinators, repel pests and much more. They also use them for self-regeneration and protection against disease. It is precisely this aspect that makes us love and value their rich health-promoting properties. But how does it work?
The chemical composition of essential oils – nature’s extraordinary magic
An essential oil, as a pure and entirely natural extract obtained through the distillation of the fragrant parts of a plant or tree, is a complex mixture of aromatic molecules, often numbering in the hundreds or thousands.
From a scientific perspective, the chemical composition of essential oils consists of mixtures of various secondary metabolites produced by the plant. The main components are:
- Terpenes
- Phenols (aromatic compounds)
- In addition to these, there are also hundreds of individual substances –lactones, benzopyrenes and various alcohols
Essential oils have a consistency similar to, yet significantly different from, that of oils. They are poorly soluble in water but readily soluble in fats, and they float on water due to their low density. Generally speaking, the chemical composition of essential oils combats bacteria and fungi, forms protective layers, helps to accelerate wound healing and much more.
Natural essential oils – how are they produced?
Before we look at the composition and content of essential oils, it is worth taking a quick look at the production process for unprocessed, natural oils.
- Steam distillation –the vast majority of essential oils we know are obtained through steam distillation. In the distiller, steam passes through the raw material – which may consist of roots, flowers or plant stems – from which the volatile molecules are then extracted. This steam is subsequently cooled, yielding a natural essential oil as well as a by-product in the form of condensed water (hydrolat);
- Extraction using a press –another remarkable method of obtaining natural oil, used exclusively for citrus fruits. The essential oil is extracted from the fruit’s peel, which simply needs to be mechanically pressed to collect the oil contained within.
Despite the effectiveness of both methods of extracting essential oils, the product obtained in this way contains only a small amount of oil. To produce 1 kg of essential oil, you need anywhere from several dozen to as many as several hundred kg of raw material! Similarly, to obtain 100 mlofbergamotessential oil,you needas much as a dozen or so kg of citrus fruit.
The composition of essential oils – how do they affect humans?
We already know that essential oils consist of a vast number of molecules of varying complexity and diversity. Research carried out over the last dozen or so years has enabled us to gain a partial understanding of the characteristics of these still-mysterious compounds and to explain what lies within the composition of essential oils.
For example, monoterpenes – the most common components of essential oils – are known for their antiseptic, calming and stress-reducing properties. Alcohols, on the other hand, exhibit active anti-infective and immunostimulant effects. Why do they affect our bodies in this way, rather than another, during massage or aromatherapy?
The answer may lie in the electron exchange that takes place within the molecules that make up essential oils, as they exchange electrons with their surroundings. Put simply, when we diffuse an oil, the molecules released into the air enter into oxidation and reduction reactions with the air or our bodies. As a result, some of them possess antioxidant properties, limiting the activity of free radicals.
Furthermore, due to the high volatility of essential oils, their components easily reach areas of the brain closely linked to the sense of smell. They can therefore trigger complex chain reactions, much like a snowball effect, thereby leading to the activation of various functions at a biological level. In other words, they enable, for example, the activation of brain areas associated with the reward system, producing dopamine, which has a significant impact on the anti-stress effects of many essential oils.
The components of essential oils – which are the best known?
The composition of essential oils is closely linked to volatile aromatic molecules. Terpenes represent the most widespread biochemical family of essential oil components. They are an excellent example of non-aromatic scent molecules, though by no means the only ones. In addition to them, there are also other biochemical families, which include some of the most valuable molecules found in essential oils. Which molecules are we talking about?
- Linalool –probably the most common naturally occurring monoterpene alcohol molecule found in essential oils. Colourless, with a floral and fresh note. As it is found in many essential oils, the scent of the molecule has not yet been correctly identified. Known for its analgesic, anti-inflammatory, calming and antibacterial properties;
- Limonene – a moleculebelongingto the group of monoterpene hydrocarbons, which creates the scent of our beloved citrus fruits such aslemonandbergamot. It is used as a flavouring agent in food and drinks, as well as in medicines! It has bactericidal, antifungal, antiviral, antioxidant and detoxifying properties;
- Geraniol –a colourless molecule with a sweet, floral scent, belonging to the family of monoterpene alcohols. As a result, the aroma of geraniol has found applications in the cosmetics and perfumery industries. Furthermore, geraniol is recognised in aromatherapy as a calming, antifungal and immunostimulant agent;
- Citronellol –a molecule belonging to the monoterpene alcohols, closely related in scent to limonene. It gives off a pleasant, citrusy scent and is characterised by extremely effective virucidal and bactericidal properties. Furthermore, it has a neurotonic effect on the body when it is exposed to chronic stress;
- Carvacrol –amonoterpenephenolwith a pleasant, spicy flavour and aroma, forming the basisof oregano. Due to its properties, it is an active ingredient in food that prevents the growth of bacteria. Indeed, carvacrol is a powerful bactericidal and anti-infective agent. It helps to relieve muscle pain and combat fatigue and insomnia.
As we can see above, these are just a few of the many hundreds of active constituents that play an active role in creating the highly effective and aromatic composition of essential oils. Their chemical composition, which includes hundreds or even thousands of aromatic molecules, has health-promoting effects proven by numerous studies, encouraging people to enjoy pleasant and beneficial forms of home aromatherapy or a massage after a hard and tiring day.
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