How are essential oils for aromatherapy extracted from plants

How are essential oils for aromatherapy extracted from plants  

The essential oils of a plant or crop usually comprise a mixture of esters. At its simplest, the oils are extracted from a plant by distillation, as employed in a standard 

To add to the cost further, many of these compounds are rather sensitive to temperature and would decompose before vaporizing. For example, oil of cloves (from Eugenia caryophyllata) is rich in the phenol eugenol (V), which has a boiling point of 250 °C). We cannot extract the oils via a conventional distillation apparatus. 

Heat-sensitive or water-immiscible compounds are purified by steam distillation at temperatures considerably lower than their usual boiling temperatures. 

Solvent extraction of essential oils tends to generate material that is contaminated with solvent (and cannot be sold) and mechanical pressing of a plant usually generates too poor a yield to be economically viable. 

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