An analysis of variance has been applied to study the individual effects and the interaction between the process parameters, temperature, pH, and surfactant concentration, in the bioscouring of cotton fibers with an acid pectinase. This study indicates that increasing the temperature does not increase the total percentage of bioscouring but accelerates the rate of the process. The pH and surfactant seem to be determinant for the optimal enzyme performance under the studied conditions. The enzyme-substrate ratio has been analyzed and a kinetic study at different enzyme concentrations has been carried out. (C) 2003 Elsevier Inc. All rights reserved.