Effect of pH on NMR transition point of sucrose concentration of high methoxy pectin

The effect of pH on NMR transition point of sucrose concentration of high methoxy pectin was studied by NMR.The results showed the NMR transition point of sucrose concentration increased as the decrease of pH.Meanwhile, the change of the structure of pectin required higher concentration of sucrose with the decrease of pH.When the pH was 2.0, 2.5 and 3.0, the transition point of sucrose concentration was 62.11% ( w /w) , 60.15% ( w/w) and 53.93% ( w/w) , respectively.