Essential Oils and Their General Aspects, Extractions and Aroma Recovery

Abstract

Essential oils (EOs) obtained from aromatic plants represent a diverse and unique source of natural products, which are widely used for bactericidal, fungicidal, antiviral, antiparasitic, insecticidal, medicinal, or cosmetic applications, especially in the pharmaceutical, sanitary, cosmetic, food, and agricultural industries. Essential oils are complex mixtures of various constituents such as phenylpropanoids, esters, and homo-, mono-, sesqui-, di-, tri-, and tetra-terpenes. Before EOs can be analyzed and their therapeutic properties investigated, it is necessary to extract the oil from different plant parts such as leaves, twigs, bark, fruits, etc. In this chapter, we will provide a general overview of the chemical diversity of essential oils, plant parts from which essential oils can be extracted, as well as the main methods of EO extraction such as hydrodistillation, steam distillation, supercritical fluid extraction, and microwave-assisted extraction.