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Have you ever wondered how essential oils are made, or rather we should say extracted? Several methods are used for extracting essential oils, with some rather basic techniques while others are relatively more complicated and difficult. We will discuss them all in detail but let’s start with their significance.
These oils have a lot of medicinal and therapeutic benefits, such as they improve sleep, reducing anxiety, relieving headaches, and even killing bacteria, funguses, and viruses. People have known the power of essential oils for years, and now they are going mainstream with their increasing availability. They are most commonly used in aromatherapy, in which they are inhaled for healing and cosmetic purposes. Since the process is simple, these essential oils can be extracted at home as well. All one has to do is purchase the copper distillation equipment and then things are pretty easy from there.
Below we have discussed in detail all the best four methods for extracting essential oils.
1 – Steam distillation
Steam distillation is the most widely used method to extract essential oils. The process is simple and it has historically been used by many people. In simple words, this technique involves the passing of steam through raw plant materials. This is the hot steam that vaporizes the plant material’s volatile compounds, which then enter a cooling chamber called a condenser unit, which then condenses them into liquid.
The liquid contains essential oil and water, which are obtained in a receiver having two separate outflows. Since the oil floats over the water, it can be collected separately and easily.
A big reason steam distillation is very popular is that the volatile compounds of plants can be obtained at temperatures lower than their boiling points. Also, the natural qualities of the oils don’t get diminished or altered during the process. That’s why this method is highly rated by people all over the world.
2 – Solvent Extraction
Solvent extraction is another very popular method that is widely used around the globe. In this process, different solvents are employed for extracting essential oils, such as ethanol, benzene, dimethyl, or hexane. This method is very suitable for delicate aromatics as they cannot withstand the pressure of steam distillation. Solvent extraction is also highly appealing as the fragrance quality through this process tends to be far greater.
In this method, we dissolve the plant into a food-grade solvent. After the oil is absorbed by the solvent, it is vapourized such that only the oil is left behind. This oil is called absolute as it contains a highly concentrated aromatic substance.
Solvent extraction produces a finer fragrance than other methods, but at the same time, it has some drawbacks as well. The main problem with this process is that small quantities of the solvent may be left behind in the absolute and that could cause irritation if someone uses it.
3 – CO2 Extraction
As is apparent from its name, this method employs carbon dioxide as the solvent. The biggest advantage of this technique is that no residue is left behind, which means you obtain essential oils that are purer and safer to use.
What happens in this process is you liquify the CO2 by applying pressure, and now this is used as the solvent for extraction. After the essential oil has been absorbed by the solvent, we restore the regular pressure which causes the CO2 to return to gas. This way, no traces of residue are left behind. Additionally, CO2 is colorless, odorless, and non-toxic.
Through the CO2 extraction method, we obtain the whole oil from the plant material. However, it has a big drawback in that the oil may contain a greater amount of pesticides than other methods.
4 – Expression
Expression is the method mostly used for extracting oils from citrus peels. This process has been used since ancient times. Originally, people would soak citrus peels in warm water and then hand-squeeze them until the oil glands burst. However, the process has become a little more technical nowadays with the use of machinery involved.
The modern expression method employs a device that punctures the citrus peels, thus releasing the essential oils which are then obtained in a collection area. The peels are mechanically pressed to release the remaining oil. Subsequently, a centrifuge is used to separate the oils from other solid materials.
Important tips for obtaining healthy essential oils
Besides the actual process of extracting essential oils, you should also follow some recommendations for obtaining good and healthy oils.
Avoid chemical fertilizers
Firstly, you should ensure that your growing plants haven’t been exposed to pesticides or chemical fertilizers. These chemicals may come into your essential oils when you start collecting them in the steam distillation method. Therefore, always avoid using chemical fertilizers on growing herbs that you later plan to extract oils from.
Harvest at the right time
It is also highly important that you harvest your plants at the right time. Usually, the time before flowering and when half of the flowers are open is the best period for harvesting.
However, this rule doesn’t apply to all the plants as some require different treatment. For example, you should harvest rosemary plants in full bloom while the best time to harvest lavender is when half of its flowers have already opened and withered.
Different treatments for different plants
Each plant is different and so they require different treatment. You can harvest annuals throughout the summer while with perennials, you will usually have to wait until September for the harvest. For herbs that grow in winter, it is important that you ensure they are free of fungus or molds, etc.
Why you should let the herbs dry before extracting oils
You should let your herbs and flowers get dry before you start using them for extracting oils. Otherwise, they remain very fragile and could crumble in your hands.
For drying your plants, you should choose an area that is warm but it shouldn’t be hot and should be placed away from direct sunlight. This is because the herbs can get damaged if they are placed in a hot environment.
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