Cal

Cal the Mexican term for calcium hydroxide or slaked lime. Corn is boiled in water with about 2 tablespoons of cal per gallon of water. The cal helps loosen the hulls and actually makes the treated corn more digestible. Cal treated corn is referred to as "nixtamal". This process of treating corn dates back to the Aztecs.Learn how to make masa

Traditionally wood ash was used but not recommended unless you are 100% sure of the content in the ash.