A centrifugal separator for separating liquid food into a light phase, a heavy phase, and an ejection phase that comprises solid impurities, the separator comprising a centrifuge bowl, an inlet for the liquid food at a bottom portion of the centrifuge bowl and outlets (104, 104') for the heavy phase and the light phase at a top portion of the centrifuge bowl, an ejection port arranged at a periphery of the centrifuge bowl to eject the ejection phase from the centrifuge bowl, a disc stack of conical discs arranged inside the centrifuge bowl, the disc stack comprising a first set of discs arranged in the bottom portion, and a second set of discs arranged in the top portion, wherein the liquid food passes the first set of discs before passing the second set of discs when received through the inlet, wherein discs in the first set of discs define interspaces in between the disks, the interspaces extending from the periphery of the disc stack to an axial center portion of the disc stack and limiting the liquid food to flow between the periphery and the center portion of the disc stack, and in that discs in the second set of discs define interspaces in between the disks and comprise distribution openings that are located between the periphery and the center portion of the disc stack for distributing a flow of the liquid food where the light phase flows from the distribution openings towards a center channel at the center portion and the heavy phase flows from the distribution openings towards the periphery, characterized by a first outlet valve that is arranged at the outlet for the light phase to increase the flow of the light phase through the outlet for the light phase when the ejection phase is ejected through the ejection port, wherein the first outlet valve is arranged to increase the flow of the light phase through the outlet for the light phase for a defined second time interval (Δt 2), wherein the second time interval (Δt 2) starts at a predetermined first time (t' s) before the ejection phase is ejected through the ejection port. a centrifuge bowl, an inlet for the liquid food at a bottom portion of the centrifuge bowl and outlets (104, 104') for the heavy phase and the light phase at a top portion of the centrifuge bowl, an ejection port arranged at a periphery of the centrifuge bowl to eject the ejection phase from the centrifuge bowl, a disc stack of conical discs arranged inside the centrifuge bowl, the disc stack comprising a first set of discs arranged in the bottom portion, and a second set of discs arranged in the top portion, wherein the liquid food passes the first set of discs before passing the second set of discs when received through the inlet, wherein discs in the first set of discs define interspaces in between the disks, the interspaces extending from the periphery of the disc stack to an axial center portion of the disc stack and limiting the liquid food to flow between the periphery and the center portion of the disc stack, and in that discs in the second set of discs define interspaces in between the disks and comprise distribution openings that are located between the periphery and the center portion of the disc stack for distributing a flow of the liquid food where the light phase flows from the distribution openings towards a center channel at the center portion and the heavy phase flows from the distribution openings towards the periphery, characterized by a first outlet valve that is arranged at the outlet for the light phase to increase the flow of the light phase through the outlet for the light phase when the ejection phase is ejected through the ejection port, wherein the first outlet valve is arranged to increase the flow of the light phase through the outlet for the light phase for a defined second time interval (Δt 2), wherein the second time interval (Δt 2) starts at a predetermined first time (t' s) before the ejection phase is ejected through the ejection port.