A methodology based on central composite experimental design is proposed in order to find the optimal operating conditions of crossflow filtration with a new product/membrane combination. This approach provides an optimal operating zone with good security and fewer pilot plant tests than usual. Interesting results are found when this strategy is applied to the clarification of raw cane sugar by using microfiltration with an inorganic membrane. Maximum fluxes are obtained with the lowest transmembrane pressures and highest crossflow velocities. Analysis of data using forward selection stepwise multiple regression is illustrated with respect to classical response surface method.