Recent advances in orange oil extraction: an opportunity for the valorisation of orange peel waste a review

Orange is a citrus plant that belongs to Rutaceae family and is widely produced and processed around the world for the production of several products, including orange juice, which is associated with the production of relatively high-volume of orange peel. This by-product is sometimes discarded as a waste in the environment. The valorisation of food waste is the point of interest and orange peel, as a food waste, can be used as a source of value added essential oil. Recently, several advanced extraction techniques, including ultrasound, microwave, enzymatic and supercritical fluid extraction, have been proposed to valorise this by-product. Each of these methods has its advantages and disadvantages and there is no published review regarding this subject. This work aims to review the recent findings on the applicability, benefits and drawbacks of orange oil extraction methods for orange peel valorisation.