Influence of damaged starch on the properties of rice flour and quality attributes of gluten-free rice bread

The effect of damaged starch (DS) content on rice flour properties and rice bread quality was investigated. Five samples containing different amounts of DS (4%, 6%, 8%, 10% and 12%) were employed without changing particle size. With the DS content increased, the fragments stripped from the surface of starch granules increased, the hydrated starch structure became loose, and the crystallinity of rice flour decreased greatly from 26.24% to 22.11%, concurrent with a decrease in the enthalpy (Delta H). Moreover, the increment of DS content caused a gradual increase in hydration properties of rice flour in cold water, an increase in viscoelastic modulus of rice batter and overall decrease in pasting viscosity. Rice bread of good appearance in terms of higher specific volume, stronger network structure, relatively soft bread texture and porous cell structure was obtained in rice flour with less DS content. Finally, it could be concluded that rice flour with 4% and 6% DS content had good flour characteristics and was suitable for gluten-free bread making.