Drying of Aromatic Plants: Processes and Effects

Aromatic plants have been used since ancient times, and traditionally they have been preserved through drying in order to extend their shelf life. The oldest way to dry foods, also applied to aromatic plants and medicinal herbs, was sun drying in open air. However, due to the development of industrial processing technologies, the drying methods evolved and in the present, modern technologies are used as a way to efficiently obtain the products while at the same time looking for the highest possible quality, i.e., preserving the aroma compounds (mostly highly volatile molecules) and also the possible bioactive molecules which provide additional value to the aromatic plants. In fact, there is a thin line between the aromatic plants and the medicinal herbs, which in many cases refer to the same plant. In view of this, the present chapter aims to address the drying procedures and corresponding operational conditions and their effects on the quality of dried aromatic plants.