PHYSICOCHEMICAL AND FUNCTIONAL CHARACTERIZATION OF CUPUAÇU BY-PRODUCTS FLOURS OBTAINED BY KILN DRYING AND FREEZE-DRYING

Cupuaçu (Theobroma grandiflorum) is widely used in the food and cosmetic industries due to its sensory and nutritional properties. Its processing for pulp production generates organic residues rich in fibers and bioactive compounds, which are often improperly discarded. Aiming at sustainability and value addition, this study proposed the production of functional flours from cupuaçu residues using two drying methods: oven drying with air circulation at 65 °C and freeze-drying. The residues were obtained from a local industry, then dried, ground, and sieved (20 mesh), resulting in two flours: FCE (oven-dried) and FCL (freeze-dried). The products obtained were analyzed for physicochemical, nutritional, and bioactive compound parameters. Physicochemical analyses showed the following average values for FCE and FCL, respectively: pH (3.54; 3.08), acidity in citric acid (10.57; 10.84 g·100 g⁻¹), water activity (0.4825; 0.5600), color L* (48.5; 86.35), Chroma (31.06; 22.30), and Hue (41.45; 89.66). The high acidity and low pH provide greater microbiological resistance, and freeze-drying resulted in a lighter and more yellowish coloration, closer to the fresh raw material. In the nutritional composition (g·100 g⁻¹, dry basis), the values were: moisture (4.13; 11.45), ash (4.75; 4.59), proteins (6.15; 7.12), lipids (5.97; 5.26), reducing sugars (41.70; 49.86), and non-reducing sugars (9.34; 20.53). Oven drying was more efficient in reducing moisture, which favors flour preservation. However, the FCE sample showed lower concentrations of proteins and reducing sugars, which may be attributed to Maillard or caramelization reactions, in which sugars and amino acids undergo thermal degradation. Regarding bioactive compounds, the results were: total phenols (273.20; 622.64 mg·100 g⁻¹), anthocyanins (1.66; 1.25), flavonoids (15.81; 11.90), antioxidant capacity by DPPH (2148.12; 1929.99 µmol trolox·g⁻¹), by ABTS (227.36; 242.55 µmol·g⁻¹), by FRAP (1064.81; 2051.63 µmol·g⁻¹), and vitamin C (ascorbic acid) (105.37; 105.20 mg·100 g⁻¹). Both drying methods proved to be viable for the production of functional flours from cupuaçu residues, promoting the sustainable utilization of these by-products. Oven drying was more efficient in moisture removal; however, freeze-drying better preserved color, nutrients, and bioactive compounds. These flours can be used to enrich foods, adding quality to the final product and reducing industrial waste.