Whole white corn was ground, and lime, water, and xylanase enzyme (0.05%, 0.075% or 0.1% w/w) were added. Blends were extruded, dried and ground to obtain nixtamalized corn flour (ENCF), which was used to make tortillas. Water absorption index and water absorption capacity (WAC) were determined in the obtained flour. Moisture content and viscoelastic characteristics (G', G'', and Tan δ) were determined in corn masa. Tortillas were made, and moisture content, texture (cutting force and rollability) during storage (2 h, 24 h, 48 h) were carried out. Tortillas of the best treatment were evaluated by sensory evaluation. The extruded flours with xylanase showed significantly (P < 0.05) WAC higher than the extruded flour control without xylanase. The viscoelastic parameters were increased by adding xylanase enzyme. There were no statistically significant differences between 0.075 and 0.1% added xylanase (P > 0.05). The addition of xylanase decreased tortilla firmness and increased its flexibility during storage. The effect was more significant at concentrations of 0.075% and 0.1% xylanase. Corn tortillas with these xylanase concentrations showed no differences (P > 0.05), and they were 15% less firm (softer) than the control. Viscoelastic parameters correlated negatively with tortilla firmness (r = - 0.99). Additionally, corn tortillas made with ENCF containing xylanase enzyme had acceptable organoleptic characteristics.
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