Effect of Dry-Milled, Wet-Milled, and Extruded Hom-Nin Rice Flours on the Quality Attributes of Gluten-Free Brownies

Abstract

The preparation methods of rice flours are very important for making bakeries. Hom-nin rice flour was prepared by dry-milling, wet-milling, and extrusion methods to determine the effect on the quality attributes of gluten-free brownies. The result showed that different flour preparation methods significantly affected the crust color, crumb color, specific volume, texture properties, and sensory attributes of hom-nin rice flour brownies. Color measurements revealed that the crust of the wet-milled hom-nin rice flour brownie exhibited the darkest compared to those prepared from dry-milled and extruded flours (p ≤ 0.05), while the crumb color of the brownies made from dry-milled rice flour showed higher L* and b* than the others (p ≤ 0.05).  Brownies made from dry-milled hom-nin rice flour showed a greater specific volume than those made with the other flours (p ≤ 0.05). Texture properties (hardness, springiness, cohesiveness, gumminess, chewiness) between brownies made from wet-milled hom-nin rice and wheat flours (control) were not significantly different (p > 0.05). Sensory evaluation showed that taste, texture, and overall acceptance of brownies made from wet-milled hom-nin rice flour were similar to the wheat flour brownie (p > 0.05). The microbial quality determined by aerobic plate count and yeast and mold count in all samples complied with Thai Community Product Standard (TCPS) 489/2555.