Production of pea protein concentrates by ultrafiltration: Influence of hollow-fibre module

The purpose of this work was to study the impact of using three 50 kDa hollow-fibre ultrafiltration (UF) membranes with different fibre lumen internal diameter (0.5, 1.1 and 1.5 mm) on the UF permeate flux and on the composition of the final concentrate. In addition to the difference in the internal lumen diameter, it was observed that the three modules also differ in terms of their intrinsic membrane resistance (1.40 x 10(12) m(-1), 1.69 x 10(12) m(-1) and 3.49 x 10(12) m(-1) for the 0.5, 1.1 and 1.5 mm diameter module, respectively). Hydraulic resistances and permeate fluxes measurement indicated that the impact of fouling is increasing with a decrease in the fibre lumen diameter. Despite the high degree of fouling observed for the 0.5 mm module, it is for this module that the highest mean permeate flux was observed. Finally, no difference in concentrate composition was observed as a function of the module used. Industrial relevance: The potential of ultrafiltration with 50 kDa membranes for the production of pea protein concentrates/isolates with improved nutritional and functional properties, when compared to concentrates/isolates produced by conventional isoelectric precipitation has already been demonstrated. However, even for a given molecular weight cut-off and module configuration, different modules are available on the market and it is conceivable that their performance in terms of permeate flux will vary due to the difference in the hydrodynamic conditions observed in each of these modules. Despite of that, there is currently no information available on the subject. So, the purpose of this work was to study the impact of using three 50 kDa hollow-fibre membranes with different fibre lumen internal diameter (0.5, 1.1 and 1.5 mm) on the permeate flux and composition of the final product. The generated information will help to improve our understanding of the impact of hollow-fibre lumen internal diameter on both aforementioned parameters and is a first step toward the successful transfer of the technology from the pilot plant to the industrial scale. Crown Copyright (C) 2012 Published by Elsevier Ltd. All rights reserved.