几种不同淀粉的物性分析研究

Study on the Physical Properties of Several Kinds of Starches

以玉米淀粉、蜡质玉米淀粉、马铃薯淀粉、马铃薯酯化变性淀粉、木薯淀粉和木薯醋酸酯淀粉为原料,比较研究了激光粒度仪和X-射线衍射仪测定的淀粉的颗粒大小和结构,快速粘度仪测定糊化特性,差示扫描量热仪和热重分析仪测定淀粉的热特性。结果表明,淀粉的平均粒径大小顺序为马铃薯类淀粉>玉米类淀粉>木薯类淀粉,且湿法和干法测定有差异;玉米淀粉、木薯淀粉和木薯醋酸酯淀粉为A型结构,蜡质玉米淀粉经过变性处理无双峰结构,马铃薯及其酯化变性淀粉为B型结构;马铃薯淀粉峰值粘度最大,热焓值最高,持水力最强,玉米淀粉的糊化温度最高,峰值粘度和衰减值最小,马铃薯酯化淀粉的起始糊化温度最低,综合持水力最弱。

Corn starch, waxy corn starch, potato starch, potato cross-linking modified starch, cassava starch and tapioca acetate starch were chosen as raw materials. Granule size, structure, pasting properties and thermal characteristics of starch were measured by laser particle size analyzer, X-ray diffraction rapid viscosity analyzer, differential scanning calorimetry and thermal gravimetric analyzer. The results showed that the average particle size of potato starch was the biggest and cassava starch was the smallest among the starch, the dry method was different with wet method. Corn starch, cassava starch and tapioca acetate starch have type A structure, potato and its modified starch have the characteristics of type B structure. The peak viscosity ,enthalpy and water holding capacity of potato starch was a high value. The pasting temperature of corn starch was the highest, and the peak viscosity and the breakdown value were the least. The initial pasting temperature of potato starch was the lowest, and the water holding capacity was the weakest.