The effects of starch/water ratio, amylose content, degree of phosphorylation, and added KI on water mobility in maize starch-water dispersions were studied by oxygen-17 spin-spin relaxation time measurements over a range of temperatures. The results demonstrate that: (i) the changes in spin-spin relaxation time (ΔT 2 ) reflect the degree of starch-water interaction at different stages of the heating process; (ii) the amount of added water affects the initial T 2 and ΔT 2 during gelatinization; (iii) higher amylose contents result in lower water mobility in starch-water systems; (iv) higher degrees of phosphorylation lead to a decrease in water mobility, accompanied by a decrease in gelatinization temperature; and (v) added KI effectively decreases water mobility and gelatinization temperature in the starch-water systems studied.