Evaluation of physicochemical changes in nixtamalized maize flours as a function of steeping time

The physicochemical properties of nixtamalized corn flours for different steeping times were studied, evaluating the particle size distribution (PSD), calcium concentration, viscosity, and crystallinity. Nixtamalized maize kernels with different steeping times were milled, dehydrated, and pulverized, which resulted in a variation in the particle size of the corresponding flours. The PSD was separated into two groups according to their percentage share in the flours: Group I (40, 60 and 80 US mesh), and Group II (30 and 100 US mesh). The calcium content increased in a nonlinear way as a function of increases in the steeping time. The greatest values were for the 100 US particle size. The maximum viscosity of the flours increased with steeping time and with diminishing particle size, for particle size greater than 30 US. The crystallinity of our samples varied from 9% to 14%, as a function of steeping time and calcium concentration. For the samples with steeping times of 8 and 9 h, the crystallinity behavior is similar: between 9% and 10.7%, respectively. The results obtained indicate that steeping time significantly improves the physicochemical properties of nixtamalized maize flours, as well as the quality of the final product.