Impact Of Different Blends Of Low-Amylose Starch Mutations and Glutenins On Wheat Flour Tortilla Quality.

Specific glutenin subunits and low-amylose starch are able to improve functional properties in wheat-derived products. However, their combined roles affecting the functionality of flour tortillas have been little studied. Null mutants for the Granule-Bound Starch Synthase (GBSS) genes in wheat genotypes result in flour with less amylose starch. Full or partial waxy genotypes are characterized by the number of null GBSS genes they contain. The combination of any one or two null GBSS genes determines partial waxy genotypes, whereas the maximum possible number of three deleted genes is called full waxy. One way to assess the contributions of specific glutenin subunits and low-amylose starch on flour tortilla quality is by blending flour from different wheat genotypes having unique combinations of these constituents. Our objective is to estimate the impact of different blends of low-amylose starch and specific glutenin subunits on wheat flour tortilla quality. Flour from twenty-two wheat genotypes with different glutenin subunits was milled and blended with flour from a full waxy wheat genotype. Four blending ratios were made for all the twenty-two combinations, in reciprocal contributions, with the following proportions: 100:0, 50:50, 25:75, and 34:66. These blends are undergoing functional evaluations for flour quality parameters. Also, tortillas from each blend will be prepared and evaluated for texture analyses, color, diameter, thickness, and density. The results from flour quality will be compared with the ones from tortilla evaluations to estimate what specific glutenins and levels of amylose are enhancing flour tortilla quality. These results will generate a model to predict flour tortilla quality based on flour characteristics.