脂肪酸不饱和度对高直链玉米淀粉-脂肪酸复合物结构和热性能的影响

本文研究了脂肪酸不饱和度对高直链玉米淀粉-脂肪酸复合物热性能、微观结构、粒径分布及Zeta电位的影响。结果表明,高直链玉米淀粉与脂肪酸形成复合物后热稳定性降低,且复合物的热稳定性随脂肪酸不饱和度的增加而降低;高直链玉米淀粉与脂肪酸形成复合物的结晶结构为V型,结晶度随着不饱和度的增加而减小;高直链玉米淀粉-脂肪酸复合物有两种存在形式,分别为颗粒表面凸起的球晶和嵌在颗粒表面的层状或絮状结构,后者存在形式随脂肪酸中双键个数的增加而减少;高直链玉米淀粉与脂肪酸形成复合物后淀粉颗粒变小,分散液稳定性增加。总之,脂肪酸不饱和度对高直链玉米淀粉-脂肪酸复合物的结构和热性能具有明显影响。

Effect of Unsaturation of Fatty Acid on Structure and Stability of High Amylose Corn Starch-Fatty Acid Complex

The effects of fatty acid unsaturation on the thermal properties,microstructure,particle distribution and Zeta potential of high amylose corn starch-fatty acid complexes were investigated. The results showed that the stability decreased when complexes achieved with high amylose corn starch and fatty acid, the thermal stability of starch-fatty acid complexes decreased with the increase of fatty acid unsaturation. The V-type crystal structure of high amylose corn starch-fatty acid complexes was formed and the crystallinity decreased with the increasing of unsaturation. There were two forms of high amylose corn starch-fatty acid complexes,which were convex spherulites on the surface of particles and layered or flocculent structure embedded on the surface of the particles,and the existence of the latter decreased with the increase of the number of double bonds in the fatty acids. The particle size of starch became smaller and the stability of dispersion increased compared with control starch. In conclusion,there was significant influence of fatty acid unsaturation on the structure and thermal properties of high amylose corn starch-fatty acid complexes.