Influence of nixtamalization cooking ingredients on the minerals composition of nixtamalized maize and sorghum

Nixtamalization is one of the identified processing techniques to reduce mycotoxins contamination in food. In this study, the effect of five nixtamalization cooking ingredients (wood ashes, calcium hydroxide, sodium hydroxide, potassium hydroxide and calcium chloride) on the minerals composition of maize and sorghum was investigated using inductively coupled plasma technology. Cooking of maize and sorghum with sodium hydroxide, calcium hydroxide and potassium hydroxide respectively gave rise to significantly (p < 0.05) highest concentration of Na, Ca, and K with all the cooking ingredients having a reducing effect on P. Maize samples cooked with potassium hydroxide had the highest level of most of the considered essential trace elements while for sorghum, wood ashes treatment brought about the richest level of Mn, Zn and V. Although some of the nixtamalized samples had unsafe Na/K ratio (sodium hydroxide treatment samples) and Al levels (wood ashes treatment samples), they all had their Cd and Pb contents below the FAO/WHO Codex Alimentarius recommended maximum levels. Generally, the study revealed that potassium hydroxide is an ideal cooking ingredient to address the low concentration of Cu, Zn and Fe common in tortillas while removal of pericarp during nixtamalization may not always bring about loss of dietary minerals