The extraction of essential plant oils through conventional methods has been used for over a century, but the use of high frequency electromagnetic field energy has been experimented as an alternative distillation method that: would reduce water consumption, reliance on non-renewable energy and very important energy sources impact on the environment. In this paper is studied the extraction microwave method of the essential oil content from two species of peppermint (mentha crispa vs mentha piperita), the differences between the two types of species and the yield. A by-product of the extraction of essential oils in the microwave field observed during the experiments is the creation of aerosols. During the experiment the ethyl alcohol (C2H5 -OH) was used as extraction solvent. In order to obtain a high efficiency and to avoid the occurrence of phenomena that would affect the integrity of the variable-power microwave generator, the system will operate in pulses, method that allows the achievement of frequencies that facilitate breakage of chemical bonds of the components.

Keywords: Microwave extraction, Essential oil, Mentha crispa, Mentha piperita