Studies and Biological Assays in Corn Tortillas Made From Fresh Masa Prepared by Extrusion and Nixtamalization Processes

: The nutritional composition and protein efficiency ratio (PER) of raw corn meal and of tortillas prepared by extrusion and nixtamalization processes were determined. Rats were fed with diets containing unprocessed raw corn meal (RCM), tortillas prepared from extruded fresh masa without lime (ET), tortillas made from extruded fresh masa with 0.25% lime content (ETWL), and tortillas made with the traditional nixtamalization method (NT). The ETWL had higher protein (8.50%) and dietary fiber (14.52%) contents than did the NT (8.15% protein and 7.39% dietary fiber). The PER value of the ETWL diet was 14.65% higher (P ≤ 0.05) than that of the RCM diet and equivalent to that of the NT diet.