部分糊化马铃薯淀粉颗粒及老化特性影响研究

Study on the Effect of Partially Gelatinized Potato Starch Granules and Retrogradation Properties

以马铃薯淀粉为原料,在不同温度下对其进行处理,制备部分糊化淀粉,研究糊化度对淀粉颗粒及老化特性的影响。结果表明,随着处理温度升高,淀粉糊化程度提高,颗粒表面变得粗糙、凹陷,部分颗粒出现熔融、团聚等现象,偏光十字逐渐消失,且糊化程度越高,此现象越明显;X-射线衍射结果表明,随着糊化度提高,淀粉的结晶度逐渐降低至完全失去结晶结构,特征峰消失呈无定形状态;热焓特性分析表明,淀粉的糊化起始温度(T)、峰值温度(T)、终止温度(T)均随着糊化度的提高而升高,糊化焓(△H)随着糊化度提高而降低。随着温度和储存时间的增加,部分糊化淀粉老化度也不断提高,其T、T、T都有所上升,老化焓也有所增加,完全糊化淀粉具有最大老化焓,为部分糊化淀粉的2~3倍。

As the raw material, potato starch is treated at different temperatures to prepare partially gelatinized starch. The effects of gelatinization degree on starch granules and retrogradation properties are studied. The results show that with the increase of treatment temperature, the gelatinization degree of starch increases, the surface of granules becomes rough and sunken, some granules start melting and agglomeration and the polarization cross gradually disappears;the greater the gelatinization degree, the more obvious this phenomenon. The results of X-ray diffraction show that with the increase of gelatinization degree, the crystallinity of starch gradually decreases until completely losing the crystal structure and characteristic peaks disappear in an amorphous state. The thermal enthalpy analysis indicates that the gelatinization starting temperature(T), peak temperature(T) and ending temperature(T) of starch increase with the increase of gelatinization degree, and the gelatinization enthalpy(△H) decreases with the increase of gelatinization degree. With the increase of temperature and storage time, the retrogradation degree of partially gelatinized starch, T, T, Tand the retrogradation enthalpy all increase. Completely gelatinized starch has the maximum retrogradation enthalpy, which is 2~3 times that of partially gelatinized starch.