不同取代度板栗淀粉磷酸酯理化特性研究

通过改变板栗淀粉酯化反应的时间,制得不同取代度的板栗淀粉磷酸酯,对其理化性质进行研究。结果表明:原板栗淀粉颗粒表面光滑,可见椭圆形、三角形、梨形等;改性后,淀粉颗粒出现不同程度凹陷、破损和裂痕。同时,随着取代度的增加,其透明度、溶解度、膨胀度增加,冻融稳定性提高。质构分析显示,改性后,其凝胶的硬度、脆裂性、胶黏性和咀嚼性降低,内聚性和黏附性增大。差示扫描量热分析显示,改性后,其糊化初始温度、吸热高峰温度和糊化最终温度降低,糊化热焓值显著变小。糊化特性显示,改性后的淀粉糊黏度提高,糊化温度降低,黏度稳定性较好。

Study on Physicochemical Properties of Phosphorylated Chestnut Starch in Different Degree of Substitution

Study on physicochemical properties of phosphorylated chestnut starch in different degree of substitution (DS). The results were as follows: the DS was increased with the extending of reaction time, and the surface of chestnut starch granule was smooth, the shape was elliptic, triangular, and irregular shape etc. However, modified the chestnut starch granules appeared sag and damaged traces, part of interior of the particles appeared to sag; the transparency, solubility, force of expansion, freeze-thaw stability of phosphorylated chestnut starch in different DS were improved significantly compared with original chestnut starch. The gelatinization temperature of the phosphorylated chestnut starch was less than that of chestnut starch, with the increase in the DS,the gelatinization temperature of the phosphorylated chestnut starch was reduced and the values of peak viscosity, minimum viscosity and final viscosity were increased. Texture profile analysis (TPA) indicated that with the increase in the DS, the hardness, frangibility, gumminess and chewiness of phosphorylated chestnut starch reduced, and the cohesion and adhesion of the increase with the DS were increased. Observed by differential scanning calorimetry (DSC), after esterification of starch, the pasting temperature decreased and the pasting enthalpy got lower and the range of pasting temperature got narrow.