不同糊化度籼米淀粉的结构及理化性质研究

Structure and Physicochemical Properties of Indica Rice Starch with Different Degrees of Gelatinization

制备糊化度分别为58%、80%、100%的籼米淀粉,探讨了糊化程度不同对籼米淀粉微观形貌、结晶特性、短程有序结构、层状结构及其热特性、黏度性质的影响。结构特性表明,随着糊化度的增加,籼米淀粉颗粒结构破坏程度加剧,双螺旋结构和分子有序排列被逐渐破坏,半结晶结构逐渐消失,结晶度由45.26%降至6.70%。热特性结果进一步证实,淀粉微晶结构随糊化度增加被破坏的程度加大,糊化峰逐渐减小,完全糊化淀粉糊化峰完全消失。其中,T_(o)及ΔT显著增加,T_(c)、T_(p)及ΔH显著增加。黏度性质表明,随着糊化度的增加,其峰值黏度、崩解值及回生值显著增加,而谷值黏度及终值黏度显著升高。

In the presentpaper,indica rice starches with the gelatinization degree of 58%,80%and 100%were prepared,and the effects of different gelatinization degree on the microstructure,crystallization properties,short-range ordered structure,layered structure,thermal properties and viscosity characteristics of indica rice starch were explored.The results of structural characteristics indicated that with the increase of the degree of gelatinization,the degree of damage to the granular structure of indica rice starch intensified,the double helix structure and the orderly arrangement of molecules were gradually destroyed,and the semi-crystalline structure gradually disappeared,and the degree of crystallinity decreases from 45.26%to 6.70%.The results of thermal characteristics further confirmed that the damage degree of starch microcrystalline structure increased with the increase of gelatinization degree,the gelatinization peak gradually decreased,and the gelatinization peak of completely gelatinized starch completely disappeared.Among them,T_(o) andΔT increased significantly,T_(c),T_(p) andΔH increased significantly.The results of viscosity properties indicatedthat the degree of gelatinization increases,the peak viscosity,breakdown and setback viscosity increase significantly,while the valley viscosity and final viscosity increase significantly.