Corn is a member of the plant family of grasses. Each kernel of corn has a highly nutritious outer layer, called pericarp. This is fused with the seed coat, typical of grasses. Although most corn has yellow kernels, they may also be black, bluish-gray, purple, green, red or white.
A corn kernel is made up of four major components: starch, fiber, protein and oil. Corn can be processed in different ways to tap into these components and used them in all kinds of products. There are two basic methods employed in processing corn kernels. They are known as “dry milling” and “wet milling.”
In dry milling, corn is separated into flour, corn meal, grits and other products by soaking corn kernels in water, then removing the germ for processing into oil. The remaining parts of the kernel are ground and sieved into various fractions. When ground, corn yields more flour with much less bran than wheat does.
Wet milling is the process by which corn is separated into starch (syrup, ethanol, cornstarch), germ (oil), and fiber and gluten (animal feed) by soaking corn kernels in water before separating them by grinding and centrifuge. In addition, refiners produce starches, sweeteners and ethanol – all made from the starch portion of the corn.
Cornstarch, which is derived from the endosperm of the corn kernel, is a mainstay of the corn refining industry. It has a wide range of industrial and food applications. Over 90 percent of the starch Americans use is produced from corn. Corn sweeteners supply more than 56 percent of the U.S. nutritive sweetener market.
All in all, one little kernel of corn does an awful lot of work. No wonder corn leads all other crops in value and volume of production.
© 2010 National Corn Growers Association Visit www.ncga.com for more details and updates on the corn industry.