Type of Corn

Corn is a member of the grass family of plants. Worldwide, corn is primarily used as livestock feed. Major commercial types of corn in the United States include: dent corn, flint corn, sweet corn, and popcorn. Specialty corns grown commercially in the United States include waxy corn, high-amylose corn, high-oil corn, and high-lysine corn.

Dent Corn - Dent corn is the most important commercial type of corn grown in the United States. The kernel of dent corn forms a dent on the crown of the kernel at maturity. Dent corn is predominantly white or yellow.

Sweet Corn - Sweet corn is grown almost exclusively for human consumption, either as a fresh product or a processed product. The endosperm (storage area) of the sweet corn kernel accumulates more sugar than that of a dent corn kernel. New advancements continue to increase the amount of sugar stored in the endosperm, with sugary enhanced and supersweet corns now on the market. The first variety of sweet corn was acquired in 1779 from the Iroquois Indians. Sweet corn comes in three colors - yellow, white, and bicolor (yellow & white).

Popcorn - The Native Americans brought popped corn to the first Thanksgiving dinner with the Pilgrims. Each kernel of popcorn contains a small drop of water. This drop of water is stored inside a circle of soft starch and a hard outer layer covers the kernel. As the kernel is heated, the water begins to expand. The expanding water builds pressure against the hard outer surface of the kernel, which eventually gives way. As the outer layer explodes, the soft starch circle inside the kernel inflates and bursts - turning the kernel of popcorn inside out. The drop of water is released as steam. There are 3 main types of popcorn kernels - white, small yellow, and large yellow. White popcorn kernels are shaped like grains of rice while yellow popcorn kernels are shaped like pearls.

Flint Corn - Flint corn has a soft, starch endosperm completely surrounded by a hard outer layer.

Waxy Corn - Waxy corn is a specialty corn that was found in China in 1908. This corn contains 100% of a form of starch where dent corn does not contain as much of this one kind of starch. The cornstarch from waxy corn is used as a stabilizer or thickener by the food industry and as an adhesive in the paper industry.

High-Amylose Corn - This is another specialty corn, producing kernels with an amylose content higher than 50%. This starch is used in textiles, candies, and adhesives.

High-Oil Corn - High-Oil corn contains 7-8% oil, 2-3% more than dent corn. High-oil corn also has enhanced protein quality and quantity.

High-Lysine Corn - High-lysine corn contains increased levels of 2 amino acids that are essential in the diet of non-ruminant animals, such as swine. The 2 amino acids are lysine and tryptophane.