The study aimed to evaluate the influence of different ultrasound (US) powers in nutritional parameters of a prebiotic soursop flavored whey beverage, comparing with the traditional dairy method of rapid pasteurization (RP). The whey beverage was manufactured with whole pasteurized and homogenized milk, whey powder, soursop pulp, sugar, inulin and gellan gum. The US processing was realized using 25-cm³ samples, for 3 min and 3 different powers (200, 400 and 600 W), one sample was submitted to RP (72–75°C for 15–20 s) and one was unprocessed (US 0 W). The samples were frozen immediately after manufacturing and stored at −18°C until the analysis. The nutritional parameters evaluated were total phenolic compounds (TPC), ascorbic acid (AA), antioxidant activity (DPPH reduction) and antihypertensive activity (ACE inhibitory values). US 200, 400 and 600 W did not significantly degraded the AA, compared with US 0 W (19, 15 and 14 mg 100 cm³⁻¹, and 18 mg 100 cm³⁻¹, respectively, P > 0.05). However, it was observed a slightly decrease in AA content of US 400 W and 600 W compared with RP (19 mg 100 cm³⁻¹, P = 0.049 and P = 0.027, respectively). The TPC values increased with both technologies (P < 0.05), and although RP, US 400 and 600 W presented similar values (750, 736 and 777 EAG mg 100 cm³⁻¹, respectively, P > 0.05), it was observed an increased extraction of TPC with US powers. The US processing (200, 400 and 600 W) improved the ACE inhibition (63, 78 and 80%, respectively) and DPPH reduction (21, 21 and 23%, respectively) compared with US 0 W (57 and 18%, respectively, P < 0.05), unlike RP (46 and 19%, respectively), that was worse than US 0 W for ACE inhibition (P < 0.05) and unaltered for DPPH reduction (P > 0.05). Furthermore, antioxidant and antihypertensive activity increased as US power increased as well. Overall, our results suggest a potential use of US technology for extracting and releasing bioactive peptides with antioxidant and antihypertensive activity, thus, improving the functional value of the product.