为了改善玉米淀粉的加工特性，提升产品品质，研究了黄原胶和3种不同链长的脂肪酸（肉豆蔻酸、棕榈酸和硬脂酸）的组合对玉米淀粉糊化性质、流变性质、凝胶性质、热性质和凝胶微观结构的影响。快速黏度分析结果表明，添加黄原胶-棕榈酸和黄原胶-硬脂酸组合后玉米淀粉糊的峰值黏度和最终黏度分别增加了123~131 mPa·s和64~94 mPa·s，回生值降低了16~18 mPa·s，而添加黄原胶-肉豆蔻酸组合的淀粉糊峰值黏度和最终黏度降低，回生值增加。静态流变结果表明，加入黄原胶和3种不同链长脂肪酸组合的玉米淀粉均表现出非牛顿剪切稀化行为（流动行为指数n<1）。动态流变结果显示，加入黄原胶-棕榈酸和黄原胶-硬脂酸组合后，玉米淀粉的储能模量G′和损耗模量G″增加，表明加入这两种组合可有效的改善玉米淀粉的黏弹性，而加入黄原胶-肉豆蔻酸组合的玉米淀粉的G′和G″值降低。添加黄原胶和3种不同链长脂肪酸组合后，玉米淀粉凝胶硬度降低了65~77 g，差示扫描量热仪结果显示在89~110 ℃出现吸热峰，表明形成了直链淀粉-脂肪酸复合物；扫描电镜观察到淀粉凝胶网络结构断裂程度增加，呈现碎片化结构，表明加入黄原胶和脂肪酸的组合后，淀粉的凝胶结构被弱化。

To improve the processing characteristics and product quality of maize starch (MS), the effects of the combinations of xanthan gum (XG) and three types of fatty acids with different chain lengths (myristic acid (MA), palmitic acid (PA), and stearic acid (SA)) on the pasting properties, rheological properties, gelling properties, thermal properties, and gel microstructure of MS were investigated. Rapid Visco Analysis (RVA) results showed that the peak viscosity and the final viscosity of MS paste supplemented with the XG-PA and XG-SA combinations increased by 123 to 131 mPa·s and 64 to 94 mPa·s, respectively, and the setback values were reduced by 16 to 18 mPa·s. By contrast, the viscosity of MS paste supplemented with the XG-MA combination was reduced, and the setback value increased. Static rheological test results show that MS supplemented with the combinations of XG and the three types of fatty acids with different chain lengths exhibited non-Newtonian shear thinning behavior (rheological behavior index n < 1). Dynamic rheological test results showed that the storage modulus G′ and loss modulus G″ of MS supplemented with the XG-PA and XG-SA combinations increased, indicating that adding these two combinations can improve the viscoelasticity of MS; however, the G′ and G″ values of MS supplemented with the XG-MA combination decreased. The gel hardness of MS supplemented with the combinations of XG and the three types of fatty acids with different chain lengths was reduced by 65 to 77 g. Differential scanning calorimetry (DSC) results showed an endothermic peak at 89 to 110 ℃, indicating the formation of amylose-fatty acid complexes in MS with the combinations of XG and fatty acids. Scanning electron microscopy (SEM) results showed that the MS gel network structure had become more fractured and showed a lot of fragmented structures, indicating that the gel structure of MS supplemented with the combinations of XG and fatty acids was weakened.

国家自然科学基金青年科学基金项目（31601504）