In this study, commercial pectinase was immobilized onto anion exchange resin particle with electrostatic adsorption. The kinetics of immobilized pectinase was studied in a batch reactor. The pectolytic activities of free and immobilized Pectinex Ultra SP-L were measured from the viscosity reduction of pectin solution at pH 4.5 degreesC and 35 degreesC. Kinetic constant were found as V-max 0.0046% (w/v)/s and K-m 1.137% (w/v) pectin for free enzyme and V-max 0.0091% (w/v)/s and K-m 2.172% (w/v) pectin for immobilized pectinase. The temperature dependence of the reaction rate obeyed the Arrhenius law. The activation energy of biochemical reaction catalyzed by free and immobilized commercial pectinase was calculated as 9.424 and 11.98 kcal mol(-1), respectively. (C) 2000 Elsevier Science Ltd. All rights reserved.