Abstract: A mixing unit (1) for mixing a liquid product (2) includes a tank (3) and a fluid nozzle (4) configured to inject a fluid flow (6, 7) of the liquid product (2) into the tank (3). The fluid nozzle (4) has a first outlet (20) that opens in a sideways direction (S), a second outlet (21) that opens in an upward direction (U), and a valve plug (14) configured to selectively open and close the outlets (20, 21). The mixing unit (1) is operable in a low stage operational mode (9) during which the first outlet (20) is open, the second outlet (21) is closed, and mixing occurs in a lower region (10) of the tank (3), and a high stage operational mode (11) during which the first outlet (20) is closed, the second outlet (21) is open, and mixing occurs in an upper region (12) of the tank (3).