Cereal Chem 44:521 - 531. | VIEW
Corn Dry-Milling: Pretempering Low-Moisture Corn.
O. L. Brekke. Copyright 1967 by the American Association of Cereal Chemists, Inc.
As determined by Beall degermination tests, the dry-milling characteristics of naturally dried yellow dent hybrid corn (about 14% moisture and under) were improved by pretempering. A pretemper step to increase the moisture content of the corn made the conventional temper more effective, largely through a reduction in number of stress cracks formed during subsequent tempering. Pretemper times of 3 to 91 hr. and pretemper moisture levels of 14 to 20% were tried. All tempering was at room temperature. Pretempering to a moisture level of 15-17% was optimal, and a pretemper time of about 20 hr. was preferred. However, a pretemper time of 8-10 hr. gave good results, and the yield of flaking grits was increased moderately with only a 3- to 4-hr. pretemper. Pretempered corn produced more flaking grits, better degermination, and a higher yield of total grits than corn having only the conventional temper. A pretemper plus a second temper also proved quite satisfactory. When screens with small perforations (14/64-in.) were used, the degerminator throughput was reduced by 30% or more on pretempered corn. With large perforations (18/64-in.) the reduction was slight, and product yields and oil contents also changed less. Pretempering was moderately effective on the artificially dried corn used.