A Conductive Microfiltration Membrane for In Situ Fouling Detection: Proof-of-Concept Using Model Wine Solutions

Cross-flow microfiltration, using a microporous membrane, is a well-established technique for wine clarification in oenology because of its cost-effectiveness and high-throughput. However, membrane fouling remains a significant issue for wine filtration in high-throughput systems. Herein, an approach for in situ real-time monitoring of fouling in filtration systems using a conductive filtration membrane and a model fluid for filtration is reported. The membrane is fabricated by embedding poly(3,4-ethylenedioxythiophene) into an electrospun sulfonated polystyrene-block-poly(ethylene-ran-butylene)-block-polystyrene microporous membrane, producing a conductive microfiltration membrane. Measurement of the resistance of the conductive membrane during filtration with the fouling solutions containing pectin, as one of the major foulants in unfiltered wine and pre-fermentation grape juice, shows a time- and concentration-dependent response. This work opens a door to new methodology for in situ monitoring of fouling processes in wine and juice filtration systems.