Effects of Rice Protein on the Physicochemical Properties of Wheat Starch

The wheat starch as raw material,differential scanning calorimetry(DSC),rapid visco-analyzer(RVA)and X-ray diffraction(XRD)were applied to determine the difference of thermal properties,pasting properties,rheological properties,X-ray diffraction and freeze-thaw stability on adding a certain ratios of rice protein to wheat starch. The results showed that adding rice protein to wheat starch made the gelatinization temperature increased,and the gelatinization enthalpy(ΔH)decreased. With the increasing of rice protein content,the peak viscosity,trough viscosity,breakdown value final viscosity,setback value of wheat starch decreased from 5266,3098,2168,4755,1657 cP to 4003,2969,1034,4439,1470 cP,and the gelatinization temperature increased from 72.50 ℃ to 76.00 ℃. Rice protein inhibited the dissolution of crystals in starch. And the addition of rice protein reduced the storage modulus and lost modulus of wheat starch gel. The gel strength was weaker,and the freeze-thaw stability was reduced.