When wife Jan recently bought me blue corn meal, she also purchased some blue masa harina. Masa harina is corn that has been soaked in calcium hydroxide (AKA slaked lime) in a process called nixtamalization. This process has many benefits, making it easier to remove the hulls, breaking down toxins that may be present in the raw corn, and altering the corn’s chemistry—allowing for easier absorption of key nutrients like niacin and letting the corn flour to absorb water to make a dough. The freshly ground corn dough—masa—is dried and then reground to make masa harina.

Blue Corn Tortillas
Tortillas on top made with culinary ash,
those on the bottom made without ash