Maize is a cereal grain that was domesticated in Mesoamerica. It is called corn in the United States, Canada, and Australia, but in other countries that term may refer to other cereal grains. It is called mealies in southern Africa. Hybrid maize is favored by farmers over conventional varieties for its high grain yield, due to heterosis ("hybrid vigor"). Maize is one of the first crops for which genetically modified varieties make up a significant proportion of the total harvest.

Maize types and qualities

Maize varies in colour, with yellow and white being the most common. Appearance and starch content classify maize and influence its use. Hybrids have enabled farmers to combine qualities from various classes, increasing their potential as food ingredients. Common types include:

• Flint maize and popcorn. Each variety has high protein content and hard outer starch layers. Dry-milled flint maize makes a very good-quality grit or meal. Popcorns are extremely hard flint varieties. When heated, water in the starch steam-pressures the endosperm to explode, swelling the small kernels and causing them to pop.
• Dent corn. The localized deposit of soft, waxy starch at the maize kernel’s crown produces a depression, or dent, in the dried kernel. Dent corn accounts for about 95% of all maize grown. The yellow variety is most commonly used as animal feed, whereas white dents go into food applications.
• Flour corn. This corn type has a soft, mealy, waxy starch and very little protein. The soft starch renders the kernels easy to grind into flour.
• Waxy maize. The starch from this maize is composed almost entirely of the highly branched form amylopectin. It is the variety used to make many food-starch ingredients.

Clic here for information on maize milling