Improving textural characteristics of tortillas by adding gums during extrusion to obtain nixtamalized corn flour

Whole white corn was ground, and lime, water and xanthan gum (XG, 0.5% w/w), carboxymethylcellulose (CMC, 0.5% w/w), guar gum (GG, 0.5% w/w) or a gums mix (XG, 0.25% w/w; CMC, 0.15% w/w; GG, 0.10% w/w) were added. Blends were extruded, dried and ground to obtain nixtamalized corn flour (ENCF), and they were used to make tortillas. The particle size distribution, particle size index, water absorption capacity (WAC) and water absorption index (WAI) were determined in flour; moisture content and viscoelastic characteristics (G′, G′′, tan δ) were determined in corn masa; tortillas were made, and texture (cutting force and rollability) and sensory evaluation were carried out. ENCF with XG and gums mix had the highest WAC, and tortillas were softer (33%) than tortillas from ENCF without gums. Corn masa viscoelasticity (tan δ) correlated negatively with tortilla firmness (r = -0.84). Corn tortillas made with XG and gums mix had acceptable organoleptic characteristics.