Mathematical Modelling of Convective Drying of Orange By-Product and Its Influence on Phenolic Compounds and Ascorbic Acid Content, and Its Antioxidant Activity Razola Díaz, María del Carmen Verardo, Vito Gómez Caravaca, Ana María García Villanova Ruiz, Belén Guerra Hernández, Eduardo Jesús HPLC-MS Orange peel Vitamin C Air-drying Polyphenols Hesperidin Orange peel is one of the main by-products from juice processing, and is considered as a promising source of phenolic compounds with anti-carcinogenic, anti-inflammatory, anti-microbial and antioxidant properties. The drying is an essential step to ensure the storage of this by-product at an industrial level, in order to use it as a functional ingredient or as a nutraceutical. Thus, this research focuses on the evaluation of the effect of the convective air-drying process in orange by-products at three different temperatures (40, 60 and 80 C) and air flows (0, 0.8 and 1.6 m/s) on the phenolic content (measured by HPLC-MS), the antioxidant activity (measured by DPPH, ABTS and FRAP), and the vitamin C content (measured by HPLC-UV/VIS). Moreover, the mathematical modelling of its drying kinetics was carried out to examine the orange by-product behavior. Among the tested mathematical models, the Page model reported the highest fit and the best drying conditions, which showed the lowest reductions were at 60 C with an air flow of 1.6 m/s and taking 315 min. 2023-03-21T11:51:28Z 2023-03-21T11:51:28Z 2023-01-21 journal article Razola-Díaz, M.d.C... [et al.]. Mathematical Modelling of Convective Drying of Orange By-Product and Its Influence on Phenolic Compounds and Ascorbic Acid Content, and Its Antioxidant Activity. Foods 2023, 12, 500. [https://doi.org/10.3390/foods12030500] https://hdl.handle.net/10481/80711 10.3390/foods12030500 eng http://creativecommons.org/licenses/by/4.0/ open access Atribución 4.0 Internacional MDPI