Citrus fruits are an important fruit crop of global importance, both in terms of commercial value and nutritional importance. They are used by the juice industry in huge quantities. The juice industry processes millions of tons of citrus fruits per year, but only the pulp is used, while the peels, seeds, and membrane residues are most often discarded. The valorization of by-products from the citrus industry, particularly orange and lemon peels, is attracting growing interest in the agri-food sector. These peels, once considered waste, have been found to be a rich source of bioactive compounds with high potential for the development of functional beverages.

The objective of this study is to incorporate citrus peel powder at different concentrations as a natural colorant and an ingredient rich in bioactive compounds to formulate a functional beverage. The peels are well dried and ground; then, they are incorporated into the formulation as an important ingredient. In addition, a complete set of physicochemical (pH, Brix, moisture, and proteins) and phytochemical (polyphenols, tannins, carotenoids, DPPH, ABTS, etc.) analyses will be carried out.

For the beverage, the results were as follows: pH—5.635 ± 0.06; moisture content—85 ± 0.056%; DPPH antioxidant activity—92.59 ± 0.04%; ABTS—80.04 ± 0.19%; polyphenol content—150.28 ± 0.04 mg/100g; carotenoid content—13.76 ± 0.15 mg/100 ml; and tannin content—60.14 ± 0.06 mg/100 ml.

These results indicate the potential to incorporate citrus peels into food products, such as in the case of our functional beverage, to enrich food products with bioactive compounds and to valorize industrial by-products.