Changes in the Physicochemical Properties of Wheat- and Soy-containing Breads During Storage as Studied by Thermal Analyses

Adding soy ingredients to baked products influences textural and sensorial properties. The changes in physical properties of bread modified with soy flour during 7-d storage at ambient temperature were investigated using thermoanalytical techniques (differential scanning calorimetry and dynamic mechanical analysis). An increase in loaf density, moisture content, and FW content, and a decrease in amylopectin recrystallization were observed with increased addition of soy flour. Addition of soy shifted the main thermal transition (0 °C, mainly due to ice melting) to slightly lower temperatures (both in differential scanning calorimetry and dynamic mechanical analysis analysis) and decreased its temperature range (increased homogeneity). These observations suggest a role for soy in modulating bread staling.