**2.3 Membrane processes**

### **2.3.1 Pressure optimization**

The juices were clarified in a PROTOSEP IV system (Koch Membrane Systems Inc., Massachusetts, USA) using a 0.3 µm (mean pore diameter) polyethersulfone membrane.

For optimization of the best transmembrane pressure to be applied, 8.0 L of conventional acid lime juice was used, operating at 0.5, 1.0 and 2.0 Bar, for 60 minutes.

For flux calculation, the volume of the clarified juice was measured each 5 minutes. The best fluxes were obtained at 0.5 Bar TMP, which was used for all the processes, in triplicate.
