The Properties of Tartary Buckwheat Starch Granules and Starch Paste

In order to determine the physicochemical characters of buckwheat starch,with 7 buckwheat varieties as ingredient,surface structure of starch granules,transparency,freeze- thaw stability,retrogradation,paste properties and thermodynamic properties of their starch granules were investigated in this study. The results showed that the starch granules of the test varieties were irregular polygonous and global shapes and average particle size of the buckwheat starch granules was 6. 8 μm. The average transparency of the buckwheat starch paste was 7. 68%,which was lower than that of corn. The starch paste retrogradation and freeze- thaw stability of the varieties tended to be higher than that of corn starch paste. The paste peak viscosity,trough viscosities,final viscosities,breakdowns and setbacks of buckwheat starch were higher than those of corn starch paste. Buckwheat starch paste had strong hot viscosity stability,cold viscosity stability and gel forming ability. The gelatinization temperature scope of the starch paste ranged from 65. 87 ℃ to 78. 41 ℃,and the peak temperature was 70. 88 ℃,which were lower than that of corn starch paste.