Fractionation of Proteins in Surimi Waste Water Using Membrane Filtration

Abstract

The study was conducted to determine the feasibility of using ultrafiltration and microfiltration for fractionation of proteins in surimi waste water. The results from this study showed that the molecular weight of the soluble proteins in surimi waste water was in the range of 10–120 kDa. Ultrafiltration surimi waste water with using membrane with MWCO 100 and 300 kDa could not fractionate these proteins since most of the proteins were retained in retentate. This result suggested that fouling formed during ultrafiltration played an important role in determination of the membrane selectivity. Improving the fouling problem may be the key factor enhancing membrane selectivity. Fractionation of proteins from this waste by using microfiltration with membranes pore size 0.22, 0.45, and 1 μm was also studied. Although some proteins could penetrate through the membrane, the results from SDS–PAGE showed that the protein profiles in the retentate and permeates did not differ, indicating that these membranes also could not be used for fractionation. This may be due to the large pore size of the membranes and the narrow range of the molecular weight of these proteins. Key words: Surimi waste water, protein recovery, fractionation, ultrafiltration, microfiltration