Cereal Chem. 70:402-404   |  VIEW ARTICLE

Wet Milling of Soft-Endosperm, High-Lysine Corn Using Short Steep Times.

E. J. Fox and S. R. Eckhoff. Copyright 1993 by the American Association of Cereal Chemists, Inc. 

Soft-endosperm, high-lysine corn was steeped for 8, 12, 18, 24, and 36 hr with 0.2% sulfur dioxide and 0.55% lactic acid at a temperature of 51 C. Laboratory wet-milling procedures were used to fractionate corn and determine product yields. As steep times decreased, the first grind required increased energy input to achieve germ separation. Shorter steep times resulted in less soluble protein release from the germ and less starch release during first grind. Even at short steep times, the germ separated cleanly with good recovery. Results of fiber separation on a Kason Vibro-screen and starch tabling were not substantially different from those of normal dent corn. As steep times decreased, there were: less solids in the steepwater, increased germ yield, constant starch yield, constant starch protein content, increased gluten protein content, increased filtrate solids, and decreased total solids released into process water. Even at 8-hr steep time, starch with less than 0.6% protein was obtained, indicating that an 8-hr steep is sufficient for soft-endosperm, high- lysine corn.