Phase Separation, Water and Thermal Properties of Andean Grain Flours andtheir Effect on Wheat Flour Dough

Abstract

Structural components and their interaction with water are fundamental to dough functionality. By studying phase-separated systems the understanding of new formulas for bakery products can be improved. The phase separation, water and thermal properties of doughs from Andean grain flours and wheat flour substituted by Andean grain flours at two levels (25% and 50%) were investigated. Amaranth, canahua, and quinoa were used. Water and thermal properties at temperatures relevant for baking were analyzed by differential scanning calorimetry. Structures and particles in dough and phases were further observed under a microscope. By ultracentrifugation, amaranth flour dough was separated into nine phases, and quinoa flour into eight. This can be compared to four for wheat flour. Canahua dough remained partially unseparated. The changes in the volume fraction of phases, thermal properties, and water properties were substantially influenced by the specific Andean grain flour and the amount used. The substitution of wheat flour by Andean grain flour at the 25% level affected the properties of the dough phases, whereas wheat flour dominated the overall phase separation into four phases. At higher levels of substitution, the separation behavior was further affected, with more phases and less clear separation. When comparing different levels of substitution, the amount of freezable water in the dough was most affected by the addition of 25% amaranth flour.