非晶化玉米淀粉的制备及其结构表征

Preparation and structural characterization of non-crystalline maize starch

为优化非晶化玉米淀粉制备工艺及表征其结构,以低温行星式球磨机研磨玉米淀粉,在单因素试验基础上,使用Box-Behnken中心组合试验和响应面分析法,对相对结晶度的主要影响因素进行多项式回归模型建立和最优化,结果表明:非晶化玉米淀粉制备的最佳工艺条件是球磨时间为2.35h,球磨机转速为482r/min,球料比为5.68:1,此时相对结晶度为1.91%.经傅里叶变换光谱仪分析球磨后的非晶化淀粉并没有新的基团产生,表征有序结构的1047cm-1特征峰消失,而表征无序结构的1018cm-1特征峰的峰形变宽.13C固体核磁共振谱分析结果表明,原玉米淀粉中有规则的双螺旋结构已解旋为非晶化玉米淀粉中的单螺旋结构.

To optimize the preparation process of non-crystalline maize starch and characterize its structure, the refrigerated planetary ball mill was employed to produce non-crystalline maize starch and the technical conditions of the ball mill were optimized using response surface test. Based on the single-factor test, the mathematical regression model was established through Box - Benhnken center composite design and response surface analysis. Then the optimum technical conditions are achieved as the milling time of 2. 35 h, the rotating speed of 482 r/min and the ratio of ball to material of 5.68： 1. Under these conditions, the relative crystallinity of non-crystalline maize starch reaches 1.91%. No new functional group is found in the non-crystalline maize starch by the analysis of FT - IR spectrogram. The characteristic absorption band of 1 047 cm^- 1 characterizing the crystalline structure of non-crystalline starch disappears, and that of 1 018 cm^-1 characterizing the amorphous structure of the starch is broadened. 13C CP/MAS NMR analysis indicates that the regular double helix structure in native maize starch has been uncoiled to the disordered single helix structure in non-crystal- line maize starch.