Mesoamerican 1500 A.D. Corn was an essential food source to cultures living throughout the Americas. A grinder like this one could be used to grind corn to make tortillas. Although corn was grown in North and Central America, the process of making tortillas, which involves mixing the crushed corn with lime to soften it up, releases nutrients and gave those living in Meso-America a nutritional advantage over those eating corn gruel in North America.