In plants, starch occurs in the presence of other elements like proteins, fibers, lipids, water and other minerals and organic compounds.  The starch grains are very small, varying from 2 to 80 micrometers and the density is high (1,600 kg / m3).

These two properties are sued to separate and purify the starch, and the manufacturing stages applied are the following:

Pre-milling

• Classification: the loading is classified according to analyses of humidity, aflatoxin, black background and GMO (genetically modified organism) of the corn samples taken.
• Pre-cleaning the corn passes through screens to remove impurities. The residues are destined to the compost unit or to co-products.
• Drying: the corn is taken to a dryer until it reaches the ideal humidity, which prevents growth of undesired microorganisms and possible cracks in the grain, in addition to increasing the efficiency of separation of the corn components.
• Storage: once dry, the corn is sent to the silos for storage, where it receives a treatment to prevent proliferation of pests. In the silo, there is a strict temperature control to prevent accidents and exposures.
• Maceration: the grains are macerated in sulfur dioxide solution under controlled conditions.
• Evaporator: During maceration, the soluble components of the grain are extracted. This water, rich in proteins and sugars, is concentrated in the evaporator that, on being added to the fibers, forms a rich ingredient for production of animal feeds.

Milling

• 1st and 2nd Milling: the first mill is responsible for the first break of the grain. The whole grains that remained from the 1st milling are broken in the 2nd milling, removing the germ still present, and the already broken grains undergo a second breaking, for easy removal of gluten and starch from the grains.
• Press: the raw oil is produced from pressing the roasted germ from the corn. It is later destarched, refined and sold.
• 3rd Milling: finest milling of corn grains. In this stage, there is a separation of gluten and starch from the fiber.
• Centrifuge: the water containing starch and gluten supply the centrifuge, which supplies heavy gluten.
• Starch modification: in this stage, the starch can undergo different modifications according to the product one wishes to obtain. The modification of starch alters properties of the final product without altering nutritional values or its composition.
• Starch conversion: The starches are hydrolyzed, resulting in products classified into three main categories: glucose, maltose and maltodextrin. The starch hydrolyzed can be sold in the form of syrup or dust.