The objective of the current study is to investigate the hydrolysis of pectinaceous matter in guava juice and to model the depectinization kinetics using commercial pectinase from Aspergillus niger. The procedure involves enzymatic treatment of guava juice at 45 degrees C with enzyme concentration (% wow) 0.033, 0.055, 0.078 and 0.1. The degree of hydrolysis of pectinaceous matter and the rate of enzymatic reaction are determined. The results show an increase in the degree of hydrolysis with time for each enzyme concentration. Depectinization kinetics reveal allosteric behavior and is modeled using the Hill Equation. The image analysis of the sample using field emission scanning electron microscopy shows a change in the smoothness and homogeneity of the sample, indicating degradation of pectin network. (C) 2017 Elsevier Ltd. All rights reserved.