Clarification of passion fruit juice by microfiltration: Analyses of operating parameters, study of membrane fouling and juice quality

► Performance of ceramic and hollow fiber membranes were compared. ► Analysis of the fouling mechanism were made using Bayesian inference. ► Permeate juice are in agreement with the current Brazilian legislation. In this study, the performance of two membranes were compared – tubular ceramic and hollow fiber poly(imide) – under transmembrane pressure of 0.5 and 1bar, for the clarification of passion fruit pulp pre-treated by centrifugation and enzymatic treatment at the concentrations of 150 and 300ppm. Nutritional and sensorial qualities of the clarified juice obtained were evaluated. Thus, it was possible to observe that the most adequate condition for the clarification of passion fruit pulp was with enzymatic treatment at 150ppm and its posterior microfiltration at the ceramic tubular membrane of 0.3μm with transmembrane pressure of 0.5bar. The fouling mechanism was identified by estimation of model parameters according to a nonlinear regression by Bayesian inference. Analysis of the fouling mechanism results revealed that hollow fiber membrane is controlled by a cake filtration mechanism, and internal pore blocking fouling mechanism controls ceramic tubular membrane.