In a broad sense, essential oils are defined as a general term for volatile substances obtained by processing and extraction from plants or animals. However, essential oils in daily use usually refer to aromatic substances obtained from botanical sources by distillation, cold pressing, solvent extraction, or maceration. Essential oils are obtained from various parts of plants, i.e., roots, leaves, seeds, bark, fruits, flowers, stems, etc. They are formed in fixed cells, most often, grouped in channels or in secretory pockets and they are then transported to the different parts of the plant during its growth. Essential oils have important biological properties such as antioxidant, antiviral, antibacterial and insecticidal. Due to these unique properties, they have applications in various fields. Today, essential oil has made an important contribution to the continuous development of the pharmaceutical, beverage, food industry, cosmetics, and perfume industries.
Methods of extracting essential oils
Essential oil extraction is one of the critical points that can affect the chemical profile of the essential oil. The main methods for extracting essential oils from plant materials are as follows.
This is the most widely used technology. Put the plant in the distilled container and heat it with water or steam. The water vapor penetrates the plant and the essential oils contained in the plant are heated into gas to escape. The vapors formed are condensed into liquid by a water-flow refrigeration system.
This is another popular essential oil extraction method. This method employs food grade solvents like hexane and ethanol to isolate essential oils from plant material. It is mainly used for more difficult to extract essential oils or essential oils with low content and fear of high temperature, such as jasmine, rose, chamomile, etc.
This is one of the oldest methods of essential oil extraction that implements the use of fat. It works on the simple principle that fats dissolve essential oils and thereby absorb their aromas. When using cold extraction, it can take more than a month, but this can be reduced to a few hours by heating.
This method, also known as expression, is particularly suitable for the extraction of essential oils from citrus fruits. This ancient process of essential oil extraction originally involved rubbing or tearing citrus peel to obtain the essential oil, which was then separated by centrifugation to separate the volatile aromatic molecules from the juice, peel solids and heavier compounds. Today, the process of extraction is a bit more technical and involves the use of machinery.
- Supercritical fluid extraction
This is one of the most modern methods. This method uses gases at their supercritical stage. The gas at supercritical stage is liquid due to the high pressure applied to it. This supercritical fluid functions as a solvent on the natural plant matter, dissolving essential oils and other substances in the plant matter. When the supercritical fluid is brought back to natural pressure and evaporated back into its gaseous state, what remains is the resulting essential oil.
Physical properties of essential oils
What we offer
Alfa Chemistry provides customers with a wide range of essential oils. If you do not find what you need, please contact us. We also offer product customization according to customer's detailed requirements.
For Research Use Only. Not for use in diagnostic or therapeutic procedures.
