Tropical Fruit Wastes: Physicochemical Characterization, Fatty Acid Profile and Antioxidant Capacity

Wastes resulting from the depulping of tropical fruits such as siriguela (Spondias purpurea), umbu (Spondias tuberosa), and juçara (Euterpe edulis) can be used as a source of bioactive compounds and nutrients. Therefore, the aim of this work was to chemically characterize the flours of siriguela seeds and peels (FSSs and FSPs), umbu seeds and peels (FUSs and FUPs), umbu pulp refine cake (FUC), and defatted juçara pulp refine cake (FJC) based on their proximate composition and mineral content, fatty acids, total phenolic content (TPC) and antioxidant capacity (ABTS•+, DPPH•, and FRAP). The results were expressed on a dry basis. The FJC had the highest lipid and protein percentage (10% and 31%, respectively), while for carbohydrates; FUS samples had the highest value (80%). FSSs presented the highest levels of Ca (239.7 mg 100 g−1), Mg (183.3 mg 100 g−1), and FSP of K (1403.9 mg 100 g−1). Regarding the fatty acid profiles, palmitic acid (C16:0) was found as the main fatty acid in FSSs (28.87%), FSPs (69.31%), and FUC (45.68%), while oleic acid (C18:1) was found as the main fatty acid in FUSs (32.63%), FUPs (48.24%), and FJC (61.58%). The FUP sample exhibited the highest antioxidant potential (1852.81 mg GAE 100 g−1, 130 µmol Trolox g−1, 131 µmol Trolox g−1, and 590 µmol Fe2+ g−1 by TPC, ABTS•+, DPPH•, and FRAP, respectively). As the first comparative study of these specific fruits wastes, the results showed that their flours are promising sources of nutrients and bioactive compounds. In addition, their use can contribute to the circular economy and Sustainable Development Goals (SDGs) 2 and 12 of the 2030 Agenda.