Abstract
In this research, the protein concentration, the permeate flux, and the predominant fouling mechanisms were investigated during ultrafiltration of different whey samples. The research was carried out at different values of transmembrane pressure and temperature using an experimental design, and a protein concentration of approximately 37 g L-1 was obtained for the bovine whey powder solution, at 60 kPa and 40 °C. The maximum flux observed was 8.9 and 7.9 kg m-2 h-1, respectively, for the bovine whey powder solution and bovine whey, at 50 kPa and 30 °C. Although goat and buffalo whey presented lower permeate flux, probably due to high solutes and calcium contents, protein concentrates of around 40 g L-1 were obtained using the ultrafiltration process. This demonstrates the potential of ultrafiltration to obtain non-bovine protein concentrates. The best fit, verified by Ho and Zydney model, suggests that the fouling for all analyzed whey occurs due to pore blocking and subsequent deposit on the membrane surface.