Eco-friendly microwave-assisted methods for essential oils extraction and their way to industrial application: A comprehensive review

Essential oils are of great interest in various industries, including food, cosmetics, perfumery, and pharmaceuticals, due to their flavoring properties and biological activities. As forecasts predict an increase in global demand for essential oils and, the industrial sector increasingly focuses on green and sustainable production methods; microwave heating has revolutionized essential oil extraction. The development of environmentally friendly, solvent-free extraction methods such as SFME (solvent-free microwave extraction) and MHG (microwave hydrodiffusion and gravity), as well as improvements to existing extraction techniques like hydrodistillation and steam distillation, illustrate this revolution. Reduced processing time, low energy consumption, and improved quality of the resulting essential oils are the main advantages of the application of microwave heating. However, adapting these methods to an industrial scale presents challenges. This article reviews the operating principles of various microwave-assisted essential oil extraction methods, as well as the advances made and challenges encountered in scaling them up to industrial production.