Converting citrus wastes into value-added products: Economic and environmently friendly approaches

Citrus fruits, including oranges, grapefruits, lemons, limes, tangerines, and mandarins, are among the most widely cultivated fruits around the globe. Its production is increasing every year due to rising consumer demand. Citrus-processing industries generate huge amounts of wastes every year, and citrus peel waste alone accounts for almost 50% of the wet fruit mass. Citrus waste is of immense economic value as it contains an abundance of various flavonoids, carotenoids, dietary fiber, sugars, polyphenols, essential oils, and ascorbic acid, as well as considerable amounts of some trace elements. Citrus waste also contains high levels of sugars suitable for fermentation for bioethanol production. However, compounds such as D-limonene must be removed for efficient bioethanol production. The aim of the present article was to review the latest advances in various popular methods of extraction for obtaining value-added products from citrus waste/byproducts and their potential utility as a source of various functional compounds. [Display omitted] •Citrus waste can come from different sources including the processing industry, biorefinery in the form of solid wastes, liquid waste, and distillery effluents.•Citrus waste disposal results in high economic costs.•Various methods are used for the valorization of citrus waste.•Citrus waste is used for the extraction of value-added product.