Occasionally wet cleaning follows to remove surface dirt, dust and other matter. The clean corn is tempered to 20 percent moisture. While moist , the majority of the outer bran or pericarp, germ, and tip cap are removed, leaving the endosperm. Further separation is accomplished using roller mills, sifters, grinding tables, and aspirators so that an infinite variety of smaller grits, meals and flours can be produced. This stream is dried, cooked, and aspirated to remove the bran.
Further processing separates the germ from any remaining endosperm.
Whole ground or stone-ground mills most often use white corn to make food products such as hominy grits and corn meal. These products are essentially whole ground corn with very little of the hull and germ removed. In the alkaline-cooked process, the corn is cooked in a boiling lime solution for 5 to 50 minutes depending on its intended use then steeped for 2 to 12 hours. The cooked and steeped corn is washed to remove excess alkali and the loose pericarp tissue. The resulting corn product is ground to form the popular masa flour.