First of all, it is postulated that pH level and acidity feature are in opposite direction; lower pH higher acidity. Second of all, as long as pH is bellow of 5.5 tooth decay occurs.
Overall, all three figures i.e. fruit sugar, cane sugar and honey, follows almost similar pattern. The acidity dramatically rises in 5 minute after eating then gradually returns to the starting level. according to the graph, cane sugar cause slower fall to 3.5 and it takes 35 min to reach the neutral level in a moderate