Mango peels as food ingredient / additive: nutritional value, processing, safety and applications

Background: It was estimated that each year, 15–25 million tons of mango peels and stones are generated. The deposition of mango byproducts in landfills cause severe environmental problems. Scope and approach: In this review, the main research encompassing phytochemical composition, processing and food industry applications of mango peels were discussed. Key findings and conclusions: In the last 5 years, 212 papers about mango peels were published. Mango peels are a great source of fiber (36–78 g/100 g of DW); vitamins (C and E); phenolic compounds (14.85–127.6 mg/gDW); and carotenoids (0.1–51 mg/gDW). One of the most promising strategies to reuse mango peels is to convert them into powders. However, drying causes losses of bioactive compounds namely, xanthones, flavonoids, alk (en)ylresorcinols and carotenoids. Excluding freeze-drying, the drying methods that best preserved the total phenolic compounds and carotenoids were infra-red and hot-air-drying, respectively. Mango peels powders were incorporated in bakery products, pastas and jellies, increasing their content of fiber, phenolic compounds and carotenoids, and improving their antioxidant activity and glycemic index. Moreover, mango peels extracts are a source of co-pigments and lipid peroxidation inhibitors. Recently, mango peels also have been reused to develop edible or biodegradable packing materials. The main opportunities for future research comprise investigation of the impact of milling methods on bioactivity of mango peel powders; determination of the best conditions to preserve them; evaluation of their food safety; and the development of technological strategies that enable a higher incorporation of mango peel powders in foods, without impairing their sensory properties.