Recovery and Functional Properties of Protein from the Wastewater of Mung bean Starch Processing

Abstract

The wet process, a conventional method for mungbean starch preparation may cause about 80% protein loss in wastewater. In this study, ultrafiltration (UF) was used to recover the protein from the simulated wastewater of mungbean starch processing. The performance and process engineering characteristics of spiral-wound modules and the functional properties of the recovered protein were investigated. The permeate flux of the ultrafiltration increased with an increase in operating pressure, and inlet temperature also enhanced it by aratio of 3%/°C. The conditions of 40°Cand 4kg/cm² were found to beappropriate for recovering proteins from the simulated was tewater. Recovery of total solids was 67.5% and 50.8% and that of protein was 87.8% and 50.3% for MWCO 30000 and 500000 membranes, respectively. Proteinremaining in the wastewater could almost be separated by UF with the MWCO 30000 membrane. The dried products from both membranes were no significantly different in their functional properties. It seems feasible to recover the protein by UF. This would not only prevent contamination but also improve the utilization of mungbeans.