Q. Are corn tortillas considered whole grain?
A. Nicola McKeown, PhD, an associate professor at Tufts' Friedman School, responds: "As a reminder, a whole grain is defined as one that has all three original parts - bran, germ and endosperm - in the same relative proportions as the original grain. For a corn tortilla to be considered a whole grain product, it must be made with whole grain corn flour, and this will be indicated on the ingredient list with words such as 'whole corn' or 'whole grain corn flour.' If the label says 'degermed corn,' it means the germ has been removed, and the product is not whole grain. In other words, you are losing some nutrients and fiber found in whole grain versions of the product.
"With that said, realize that in traditional cultures of Central and South America, corn masa tortillas are made by first soaking the corn in lime water [referring to the mineral lime] in a process called nixtamalization. While this process boosts the nutritional value of the tortilla, mainly by making B vitamins more bioavailable, a small amount of bran is lost during soaking." Because of this loss, some US regulatory agencies, including the FDA, don't consider corn masa a whole grain. However, it is still a good choice.