Effect of thermal-alkaline processing conditions on the quality level of corn oil

The objective of this study was to determine the best combination of process variables to produce nixtamalized corn flour (NCF) with the lowest level of lipid deterioration. The nixtamalization conditions used were calcium concentrations from 0.4 to 2.56 g Ca(OH)(2)/L in water and steeping times of 6.34 to 17.65h. The cooking time was 40min at 94 degrees C. The cooked and steeped grains were washed and milled to obtain masa which was then dehydrated and milled until the NCF was obtained. Oil was extracted by means of hexane from each sample of processed corn. The level of least oil deterioration of nixtamalized samples was based on the following response variables: saponification, acidity, peroxides, iodine values and extinction coefficient measured at 270nm (K-270). The best nixtamalization conditions for obtaining the highest oil stability were found at Ca(OH)(2) lower than 0.75% and steeping times less than 12h.