SEPARATION OF STARCH AND GLUTEN: III. A RAPID METHOD OF SEPARATION FROM WHEAT FLOUR

Abstract

Patent flour was mixed with sufficient water to form a smooth coherent dough, which was subsequently broken up into curds by agitating with additional water. Primary separation of the starch suspension and crude gluten was effected by passing the slurry over an inclined gyrating screen of about 150 mesh. Starch was recovered from the suspension by means of a basket-type centrifuge and dried. More than 90% of the starch containing less than 0.5% of protein was recovered. Substantially complete recovery of the gluten having a starch content of about 20% (dry basis) was realized. The crude gluten could be readily refined by shredding, washing, and rescreening. When dry, it contained 70 to 75% of protein and 10 to 12% of starch.A study of the effects of the processing factors has shown the following permissible ranges: amount of water for dough-mixing, equivalent to 80 to 85% of the weight of flour; temperature of the water for mixing, 25° to 30 °C.; time of dough-mixing, 15 to 20 min.; time of dough agitation in water, 1 to 4 min. A portion of the dough-mixing time could be replaced by a dough-conditioning period. The most critical factors were the flour–water ratio and the time of dough-agitation.The method effected a rapid and efficient separation of the starch and gluten fractions and should be adaptable to continuous large-scale operation.