Post-harvest handling is the next stage of maize production immediately after harvesting. This is done to keep cool, avoid moisture loss and slow down undesirable chemical changes as well as avoiding physical damage of maize output. Stages involve in post-harvest handling include pre-drying in the field, threshing, winnowing, drying, storage of grain. Post-harvest handling is also called pre-processing.

Maize harvesting can be done either by mechanized or manually. The mechanized system removes not only the ear from the plant but also the grain from the cob, while manual harvesting requires initial removal of the ear, which is shelled at a later stage. In both situations, maize is usually harvested when its moisture content is in the range of 18 to 24 percent. Damage to the kernel is related to moisture content at harvest; the lower the moisture content, the less the damage.

There are different methods of drying maize which include the following:

Layer drying: In this method, the harvested grain is placed in a bin one layer at a time. Each layer of grain is partially dried, before the next is added, by forcing air through a perforated floor or through a duct in the bottom of the bin. To improve efficiency, the partially dried grain is stirred and mixed with the new layer. An alternative is to remove the partially dried grain and dry it completely in batches. One of the problems with this and other methods of drying is in finding a way to mix low-moisture grain with high-moisture grain to get the desired equilibrium in the final product.

Portable batch dryers: Since drying installations are costly, few maize producers, particularly small farmers, can afford to have their own. Portable batch dryers are useful since they can be moved from farm to farm. These dryers operate with air heated to 140 to 180°F (60 to 82°C).

Continuous flow dryers: These dryers ensure continuous flow of grain through heated and unheated sections so that it is discharged dry and cool.

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