Effect of the Pore Size of Glass Membrane on Cross-flow Microfiltration of Beer

The cross-flow filtration method was applied to fermented beer by using 6 glass membranes with pore size 0.23-3.0 μm, in order to estimate the possibility of replacing dead-end filtration by cross-flow filtration. The effect of the pore size on filtration characteristic was examined and following results were obtained. The filtration time and filtration process required to the steady-state were different depending on the pore size. As the ratio of cake layer resistance to total permeation resistance was increased to greater than 90%, the flux was directly affected by cake layer resistance. The fermented beer had numerous small particles ranging in sizes less than 1μm, and the bigger the pore size was, the more particles were allowed to pass through the membrane, whereby decreasing the plugging resistance. These particles caused the beer turbidity. Membrane pore size of 0.72μm was found to be suitable for beer crossflow filtration from the point of filtration performance and filtrate quality. However, at present, it was impossible to replace the conventional method with crossflow filtration due to poor filtration capacity even though 0.72μm membrane was applied.