Maize that underwent nixtamalization was ground down into a much, much finer powder (called masa flour) than most Americans might be used to seeing. In the states, we're most familiar with cornmeal, dried ground corn that did not undergo this special method.
Whats the difference? Cornmeal cannot be made independently into a dough while masa flour only needs the addition of water and salt. There is also a key difference in nutrients.
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