Maize: Wet Milling

The corn (maize) wet milling process begins with steeping the corn kernels in an aqueous solution that contains varying amounts of sulfur dioxide and lactic acid for a period of 24–48 h at 50–55 °C. This prepares the kernel for milling, separation, and other downstream processes. Germ is recovered using hydrocyclones, fiber is recovered by pressure-fed screens, and starch and protein are separated using hydrocyclones. Corn germ, gluten feed, gluten meal, and starch are high-valued coproducts that are marketed by the corn wet miller.