Updated: April 28, 2022
People have stopped smelling the roses for ages!
The enormous variety of aromatic plants and their scents has enchanted us for thousands of years. It's no wonder we figured out how to extract the scent and take it with us wherever we go!
Depending on the plant and the part of the plant we want to extract, we may need to use more than one extraction method. Below are descriptions of the most common methods used to extract essential oils: steam distillation, cold pressing, and solvent extraction.
steam distillation
Steam distillation is the most common method of extracting essential oils from the plant.
Fresh or dried plant matter is placed in an alembic and pressurized steam is circulated through the plant matter. The heat from the steam opens up the specialized cells or glands to release the essential oils. As the essential oil is released, it travels along with the vapor molecules through a hose into the still's condensation chamber. As this mixture cools, it condenses into oil and water. The essential oil then naturally separates from the water.
Steam distillation provides a very "pure" form of essential oil as only water and heat are used in the extraction process. Steam distillation is used for many flowers and foliage, such as lavender, ylang-ylang, and peppermint. It is also used for woody plant and tree oils such as cedarwood. This type of distillation can also be used for delicate flowers like rose.
cold pressing
In this method, the skin of the fruit is grated as it rolls down a chute. The tiny specialized cells that contain the essential oil are punctured. Then the fruit is pressed to extract the juice and essential oil from the pulp. The essential oil rises to the top of the juice and is then separated by a centrifuge. We saw this process in Italy with bergamot, and it was amazing to watch (and smell). Here are some pictures.
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The cold press machine that produces the delightful bergamot oil.
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The distiller puts the bergamot fruit on the conveyor belt to be rinsed and rubbed.
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The fruits are washed and sent to the grater.
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The fruit peels are grated as the essential oil is concentrated in the peel.
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The essential oil from the