The aim of this work is to study the physicochemical characterization of commercial instant corn flour (CICF) and traditional instant corn flour (TICF) prepared with threshed corn. The chemical analysis shows that there are a few amounts of fat, fiber, and minerals but the protein shows small variations in relation to the threshed corn. The CICF is characterized by coarse particles. Differential scanning calorimeter corroborated that the flours are gelatinized; but in the case of CICF the starch granules are partially disrupted and some of them are integer, producing structural changes which are identified using X-ray diffraction. A pasting analysis based on the pasting curves was conducted in order to study the apparent viscosity of these flours. The CICF shows quick water absorption at low temperatures and major values in peak viscosity than the threshed corn flour which may be related to presence of hydrocolloids. The TICF apparent viscosity showed a complete gelatinized starch.