HYDROCYCLONE PROCEDURE FOR STARCH-PROTEIN SEPARATION IN LABORATORY WET-MILLING

A hydrocyclone system for starch-protein separation was developed for use with 1-kg samples in laboratory corn wet milling. A Doxie 5 hydroc yclone with all but one cyclone plugged and a five-pass starch washing system was compared to a traditional starch tabling procedure using b oth regular dent and waxy corn hybrids. The tabling procedure gave 3-4 % higher starch yields in dent corn and 2-3% higher starch yields in w axy corn. Tabled starch had less protein (0.33 and 0.45% for dent and waxy, respectively) than the Doxie 5 hydrocyclone-separated starch (0. 64 and 0.65% for dent and waxy, respectively). Using a Doxie Type A si ngle hydrocyclone instead of the Doxie 5 increased the starch yield; h owever, protein in starch increased to 1.29 and 0.97% for dent and wax y, respectively. Design and operational differences may account for th e different results. The hydrocyclone procedure reduced the time requi red for starch-protein separation by 75%. It also eliminated the requi rement of a large floor area for starch tables, reduced the potential for operator error, and more closely simulated the starch-protein sepa ration process used in industrial operations. The reduced testing time and ease of use will make the hydrocyclone procedure useful for compa ring milling procedures or different corn hybrids.