湿热处理对板栗淀粉结构及理化性质的影响

Effect of Heat-Moisture Treatment on the Structure and Physicochemical Properties of Chestnut Starch

以板栗淀粉为对象,采用湿热处理方法对板栗淀粉进行物理改性,通过控制湿热处理的时间(2~18 h)、温度(80~120℃)、含水量(10%~30%),制得不同处理条件下的板栗淀粉。随着湿热处理程度的加强,板栗淀粉的溶解度、膨胀度均减小,其中,处理温度的影响较大;湿热处理后板栗淀粉的透光率下降;板栗原淀粉颗粒的表面光滑,多数呈椭圆形、梨形等;湿热处理后,淀粉颗粒大部分保持原状,但部分颗粒表面出现轻微的凹陷和破损;X-射线衍射图谱显示虽然淀粉结晶型仍为C型,但淀粉颗粒内部有新的结构出现。

Chestnut starch was taken as the experimental material. Heat -moisture treatment （HMT） was used for physical modification on chestnut starch under various conditions, including time（2 - 18 h） , temperature （80 120 ℃ ） and humidity （ 10% - 30% ）. As the increasing of heat - moisture treatment, the degree of solubility and swell capacity of chestnut starch decreased and was significantly influenced by temperature. On the other side, HMT led to the decline of its transparency. Native chestnut starch granules exhibited a smooth surface with varied shapes （ usually oval or pear - shaped）. However, the granular structure of modification was destroyed after being heat - moisture treated, and led the loss of granular appearance and to a irregular shape. X - ray diffraction analysis indicated that modified starch had C crystallization type as well as the native one. But there appeared new structure in modified granular, then led the change of physicochemical properties of native starch.