Tortillas of blue maize ( Zea mays L.) prepared by a fractionated process of nixtamalization: analysis using response surface methodology

Abstract

In the present study an alternative to the traditional nixtamalization process was studied. Pericarp, tip cap and germ (PGT) were separated from the endosperm in a prototype decorticating device. The fractions were nixtamalized in an intermittent blender using steam injection. First the PGT fraction (18.2%) was nixtamalized in an alkaline solution (0.29–1.71% w/w) of boiling water, in a proportion of 1:1 (alkaline solution:PGT), The endosperm fraction (81.8%) was then immediately added to the same container, mixed thoroughly and kept at constant temperature of 92 ± 2 °C, for cooking times from 9.2 to 51.2 min. The nixtamalized fractions of maize were dried at 60 °C for 5 h and milled. Tortillas made from nixtamalized flour prepared with 1.0% (w/w) calcium hydroxide and a nixtamalization time of 45 min showed functional characteristics similar to the traditional blue tortilla.