Abstract: A centrifuge for separating, in a massecuite, a quantity of sugar crystals from a syrup, the centrifuge including at least: a centrifuge basket into which the massecuite is intended to be introduced, and which has a peripheral wall; a measurement device including at least one light source designed to illuminate the peripheral wall over at least 90% of its height; and a photodetection system designed to detect light reflected by the peripheral wall over at least 90% of its height and to deliver photodetection measurements which are representative of the massecuite accumulating on the peripheral wall or of the peripheral wall itself; and a processing unit connected to the measurement device and designed to continuously process the photodetection measurements in real time.