The kinetics and operational behavior of a nylon membrane derivative with immobilized pectolytic enzymes in a cross-flow reactor were analyzed. A high dependence on the recycling flow rate was observed. A design equation of the system has been proposed by taking into account both the shear stress deactivation and the control of the external diffusional limitations. Integration of the resulting design equation allowed us to study the effect of different operational parameters on substrate conversion. The catalytic efficiency of the immobilized derivative in a cross-flow reactor showed the highest pectin hydrolysis capability when it was compared with two different configurations of packed-bed reactors.