Effects of White Sorghum Flour Levels on Physicochemical and Sensory Characteristics of Gluten-Free Bread.

Abstract

This research studied the effects of white sorghum flour levels at 0, 10, 25, 40, 70, 85 and 100% in the matrix of rice and tapioca flours and corn starch on the properties of flour blends and the qualities of gluten-free (GF) bread. Single and composite flours were analyzed for moisture content, color and pasting properties. GF bread samples prepared from composite flours were analyzed for specific volume, moisture content, water activity, crumb color and instrumental texture. Sensory profiles of the breads were determined by nine trained descriptive panelists. The results show that increasing the sorghum flour content increased (p ≤ 0.05) color intensity, pasting temperature and setback viscosity, while it decreased (p ≤ 0.05) the peak and breakdown viscosities of flour blends. For GF bread, increasing white sorghum flour levels in the blends primarily affected specific volume, color, flavor and texture characteristics, leading to decreases (p ≤ 0.05) in specific volume, cohesiveness, springiness, chewiness and moistness, but increases (p ≤ 0.05) in color intensity, brown and nutty flavors, graininess and roughness. White sorghum flour could be used in the blends at the maximum level of 25% to get a good bread volume without sacrificing texture quality.