The Ultimate Guide to Essential Oil Extraction Methods: Steam Distillation, Expression, and Solvent Extraction
Essential oils have been used for thousands of years in different cultures. These are compounds extracted from the seeds, bark, stems, flowers, fruits, roots and other parts of plants.
Every plant has its unique aromatic compounds. The oils capture the scent and flavor of the plant and give its essential oil its distinctive and characteristic smell. Because of their medical properties, essential oils are recently gaining popularity as a natural beauty treatment and health-care practices.
There are three main types of extraction methods. Some extraction methods are best suited to particular plant types and parts.
Steam Distillation
Steam distillation is a separation process used to purify natural aromatic compounds. During this process, the plant material are placed in a still. The hot steam needs to be hot enough to allow the release of the essential oil but not damage the plant material. Then the steam with essential oil passes through a condenser which is a cooling system where the steam condenses into a liquid. The liquid consists both essential oil and water, also called pure hydrofoil or floral water. Use a separator to separate the esstensbal oil from water.
Lavender essential oil produced by Lavender Backyard Garden are extracted from steam distillation. Click this article to see how we distill our lavender essential oil.
Expression
Expression is also called a "cold pressed" method. Since citrus oils do not hold up well when it is heated and the its peels need to be pierced and squeezed, Cold Press is the better way to obtain citrus oils. In this process, the oil is forced from the plant material under high mechanical pressure.
Solvent Extraction
Some plant materials, such as vanilla and rose petals, are either too difficult to extract or too delicate to survive through the process of distillation. To extract its essential oils we need to use another method, called solvent extraction, to extract their aromatic essence. This process utilizes petroleum solvents or alcohol solvents. As the solvent is added to the plant material it is absorbed and allows the aromatic compounds to be released.
Types of Essential Oil Extraction Methods
In summary, here are three types of essential oil extraction methods:
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Steam distillation is a method used to purify natural aromatic compounds by passing hot steam through plant material and condensing it into a liquid.
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Expression, also known as cold pressed method, is a process that is best suited for obtaining citrus oils by forcing the oil from the plant material under high mechanical pressure.
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Solvent extraction is a technique used for delicate or difficult-to-extract plant materials by adding solvents to the plant material, allowing the aromatic compounds to be released and then separating the oil from the solvent.
The award-winning lavender essential oil produced by Lavender Backyard Garden.
