Essential Oils: Benefits, Properties and Use of Natural Essences
Man has always sought a way to capture the fragrance of plants, that volatile and invisible aroma that connects us to deep memories and sensations. Today we know that fragrances can influence our mood and well-being, thanks to essential oils, precious substances extracted from various parts of plants. But how do they work? What is their biological purpose and how can we make the best use of them?
What Is an Essential Oil?
Essential oils are highly concentrated aromatic compounds found in specific parts of plants: flowers, leaves, roots, fruits, bark and resin. These oils play an important role for the plant itself, protecting it from bacteria, fungi and parasites, as well as promoting reproduction by attracting pollinating insects. For example, the fragrance of rose and jasmine flowers attracts beneficial insects, while the scent of thyme and sage helps repel harmful parasites.
The Production of Essential Oils in Plants
In the past, it was thought that essential oils were a byproduct of plant metabolism. Today, research has shown that these compounds have vital functions. Plants use essential oils not only to defend themselves against external agents, but also to modify the surrounding microclimate by regulating humidity and temperature. For example, the essential oils found in citrus peels, such as orange and lemon, help protect the fruit from excessive heat.
Where Are Essential Oils Found?
Essential oils are found in various parts of the plant, each with specific characteristics:
- Flowers: rose, jasmine, chamomile
- Leaves: sage, lemon balm, thyme
- Roots: calamus, angelica, vetiver
- Fruits: anise, coriander, cumin
- Wood: sandalwood, cedar, rosewood
- Bark: cinnamon
- Resin: frankincense, myrrh, benzoin
- Fruit peel: orange, lemon
Extraction of Essential Oils
To extract just a few drops of essential oil, a large amount of plant material is required. During the extraction process, it is essential to keep the container tightly sealed, as essential oils are extremely volatile. This means that they tend to evaporate quickly, "returning to the sky", as suggested by the etymology of the term "ethereal", which derives from Greek and means "celestial".
Essential oils are not oily like cooking oils, such as almond or jojoba oil. On the contrary, they are light and volatile, evaporating easily without leaving oily residues.
Storage of Essential Oils
To preserve the properties of essential oils, it is essential to store them correctly. Being photosensitive, they must be kept in dark glass bottles, preferably brown, to protect them from UV rays. If stored correctly, essential oils can last for several years. However, the quality of some oils, such as citrus oils, can deteriorate more quickly and, for this reason, it is advisable to store them in the refrigerator.
The ideal storage temperature is between 5°C and 30°C. Once a bottle is opened, it is important to avoid oxidation by keeping it as full as possible.
Viscosity and Mixing
Essential oils can have very different consistencies. Some, such as lavender and lemon, are very fluid, while others, such as vetiver or mimosa, are denser and require the use of a spatula to extract them. Furthermore, these oils do not mix well with water but combine easily with fatty substances such as vegetable oil, alcohol, or natural emulsifiers such as milk, honey, and egg yolk.
Use of Essential Oils in Aromatherapy
There are hundreds of aromatic plants, but essential oils can be extracted from only about 700 of them. In aromatherapy, however, 70 oils are mainly used, among the best known and most effective for physical and mental well-being. Essential oils such as jasmine, patchouli, and frankincense improve with age, while others, such as citrus oils, are more delicate and require use within a shorter period to ensure maximum effectiveness.
