Physical properties and enzymatic digestibility of hydroxypropylated ae, wx, and normal maize starch

The physical properties and enzymatic digestibility of hydroxypropylated starches prepared from high amylose (Hi-Maize(TM), 66% amylose; GELOSE 50, 47% amylose), waxy (MAZACA 3401X, 3.3% amylose), and normal (22.4% amylose) maize starches were studied. For normal and high amylose starch, hydroxypropylation decreased the temperature at peak viscosity and caused a large increase in both the peak and cool paste viscosities. Hydroxypropylation had little effect on the pasting properties of waxy starch. All the hydroxypropylated starches had lower gelatinization parameters (To, Tp, Tc, and DeltaH) than their unmodified and control starches, but hydroxypropylation increased swelling power and solubility. After hydroxypropylation, the hardness and adhesiveness of all the starch gels decreased. Hydroxypropylation increased the clarity and enzymatic digestibility of all the starches.