蛋白组分对籼米粉糊化特性的影响机理探讨

Protein Fractions on Pasting Properties of Non-waxy Rice Flour

摘要:

通过逐一去除蛋白组分的方法研究了蛋白组分对籼米粉糊化特性的影响，并分析了影响这些变化的蛋白结构基础。RVA和DSC分析结果表明，不同组分的蛋白在去除之后，峰值粘度、热糊粘度和最终粘度均有不同程度的升高，崩解值、回生值及糊化温度均有不同程度的降低。SDS-PAGE和显微结构分析表明，各组分对糊化特性的影响机理应有差异：谷蛋白通过与纤维素类物质的紧密结合，在糊化过程中阻碍淀粉粒的溶胀；醇溶蛋白可能是通过蛋白体自身的溶胀与淀粉相互作用而影响；清、球蛋白通过活性蛋白对籼米成分的水解或合成等改变而影响；淀粉粒结合蛋白则可能对籼米的基础糊化特性影响较大。与分离重组法比较，逐一去除蛋白组分的方法因为蛋白组分之间的相互作用影响较大，对糊化特性的影响与分离重组法略有差异。

Abstract:

Protein fractions on pasting properties of non-waxy rice flour were investigated through the fraction removed method, as well as the protein structures were analyzed. The results of RVA and DSC indicated that the peak viscosity, hot paste viscosity and final viscosity increased in different degree after the treatment, while the breakdown, setback and paste temperature decreased. The results of SDS-PAGE and microstructure analysis demonstrated that the mechanisms of pasting property affected by protein fractions were distinct: because binding to cellulose tightly glutelin lead to repel the swelling of starch granule, prolamin absorb water to swell and interact with starch, albumin and globulin hydrolyze or synthetize the rice component through bioactive constituents such as enzyme, starch granule associated protein affect the intrinsic pasting property of non-waxy rice flour. Compared with isolate and reconstitute method, the fraction removed method have more protein interaction, which lead to the diversity of the pasting value.