FYI: Why "cal" is in tortillas...

The ancient Aztec and Mayan civilizations developed nixtamalization using slaked lime (calcium hydroxide) and ash (potassium hydroxide) to create alkaline solutions. The Chibcha people to the north of the ancient Inca also used calcium hydroxide (also known as "cal"), while the tribes of North America used naturally occurring sodium carbonate or ash.

The nixtamalization process was very important in the early Mesoamerican diet, as unprocessed maize is deficient in free niacin. A population depending on untreated maize as a staple food risks malnourishment, and is more likely to develop deficiency diseases such as pellagra. Maize also is deficient in essential amino acids, which can result in kwashiorkor. Maize cooked with lime provided niacin in this diet. Beans, when consumed with the maize, provided the amino acids required to balance the diet for protein.

https://en.wikipedia.org/wiki/Nixtamalization