Mint (Mentha spp.) essential oil extraction: from conventional to emerging technologies

Mint essential oil (MEO) is an economically appreciated natural product with significant importance in the cosmetics, pharmaceutics, foods, and healthcare products due to its biological activities. Extraction is a critical step in the production of essential oils from aromatic plants, such as mint. Conventional extraction approaches, such as steam distillation and solvent extraction are commonly used for the extraction of MEO. However, they are energy and time-consuming processes with relatively low extraction yields. Consequently, emerging techniques, such as microwave-assisted, ohmic-assisted, ultrasound-assisted, pulsed electric field, and super and sub-critical fluid extraction methods have been developed to overcome these shortcomings. This review aims to investigate the influence of different extraction methods and conditions on the extraction yield, composition, physicochemical properties, and bioactivity of MEO. Overall, selection of appropriate extraction method and conditions is a crucial step in the extraction of MEO that can have significant effects on the quality and quantity of the isolated EOs. Inappropriate extraction of MEO may reduce the extraction yield, prolong the extraction duration, and increase the energy consumption. Additionally, it may deteriorate the physicochemical properties and bioactivity of the extracted MEO.