The pH dependence of the shear viscosity at g_Z10 sK1 (h10), is shown in Fig. 1 The pH was adjusted by adding various acids before gelatinization. h10 decreased by lowering the pH to around 5.6 and increased inversely at 3.6!pH!5.6. By lowering the pH furthermore, h10 decreased again. The values of h10, where the pH was above 5.5 and below 3.6, were less than that of the control, and the values of h10, where the pH is between 5.5 and 3.6, were greater than that of the control.