研究明胶与甜菜果胶形成的复合物受pH值和混合比例的影响。甜菜果胶与明胶总质量浓度为0.1 g/100 mL时,在两者一定的混合比例下,添加葡萄糖酸内酯进行酸化,利用紫外-可见分光光度计、激光纳米粒度及电位滴定分析仪,测定体系的浊度、散射光强和流体力学半径。通过寻找特征pH值,确定相边界,进而构建体系的pH值-混合比率相图。结果表明:明胶与甜菜果胶混合物在酸化过程中,在高pH值区域无相互作用,随后形成分子内可溶性复合物,进一步酸化形成分子间可溶性复合物,在低pH值区域为不可溶性复合物,体系逐渐失稳。
Factors such as pH and mixing ratio for in?uencing the complex of sugar beet pectin and gelatin were studied.The total concentration of sugar beet pectin and gelatin was ?xed at 0.1 g/100 mL. At a certain mixing ratio, the mixedsystem was acidi?ed by gluconolactone, and the turbidity, light scattering intensity and hydrodynamic radius of the systemwere determined. Through exploring featured pHs, the phase boundaries were determined and a pH-composition phasediagram was established. The turbidity was measured using UV-Vis spectrophotometer, and light scattering intensityand hydrodynamic radius were tested using Zetasizer Nano-ZS apparatus. Based on the phase diagram and microscopicobservation, no interaction was found between sugar beet pectin and gelatin at higher pH levels, while intramolecularand subsequently intermolecular soluble complexes were formed due to further acidi?cation. At low pH levels, insolublemolecular complexes were developed and the system became unstable.