17C-10 |
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M. C. ENRIQUEZ-LEAL1, V. Santana2, F. R. Del Valle3, J. Jimenez2, and E. Seaņez2. (1) Facultad de Ciencias Quimicas, Universidad de Autonoma de Chihuahua, Ciudad Universitaria, Chihuahua, Chihuahua, 31240, Mexico, (2) Facultad de Ciencias Quimicas, Universidad Autonoma de Chihuahua, Ciudad Universitaria, Chihuahua, Chihuahua, 31240, Mexico, (3) Dept. of Chemical Engineering, New Mexico State Univ., PO Box 30001, MSC 3805, Las Cruces, NM 88003-8001 Corn tortillas reflect a serious quality problem: they become brittle upon storage. Tortilla flexibility may be partially preserved by incorporation of hydrophilic gums or mono- and diglycerides, and also by cross-linking. However, these procedures are costly for developing countries. An inexpensive possibility for cross-linking tortilla starch could be establishment of calcium ion bridges. Calcium ions are incorporated into tortillas during the nixtamalization process, and calcium ion concentration could be further increased by addition of calcium chloride. The objective of this research, therefore, was to test the hypothesis that tortilla flexibility could be increased by addition of calcium chloride. Other objectives were to determine the effect of calcium chloride on masa quality parameters. A 2 x 2 x 3 experimental design, with replication, was utilized as follows: white and blue corn varieties; 1% and 3% lime concentrations; 0%, 1% and 3% calcium chloride concentrations. The corn samples were processed according to the traditional nixtamalization process, the nixtamalized corn was dried (65 C, 10% moisture) and ground into a flour (40-mesh), and the flour was mixed with water in order to obtain a masa, from which tortillas were prepared. The following quality parameters were determined: masa yield (kg of standard consistency masa/kg flour); masa cohesiveness (breaking weight of a vertical extruded column of masa); and tortilla flexibility. Results were analyzed by ANOVA and regression techniques. Addition of calcium chloride did not significantly affect flexibility, masa cohesiveness was a qudratic function of calcium chloride concentration (av. R2=0.80; maximum cohesiveness at 1% concentration), and masa yield decreased linearly with increasing calcium chloride concentration (p<0.05, R2=0.97). The white corn tortillas were more flexible, and the most cohesive masas were obtained from both varieties of corn flours prepared with 1% lime concentrations (p<0.05). It appeared that both masa and cohesiveness were significantly affected by incorporation of calcium chloride, but that tortilla flexibility was not significantly affected by this substance.
Session 17C, Food Chemistry: Cereals, grains, legumes and their products
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