Abstract: A process for producing thermally inhibited starch is described resulting in a viscostable starch product. The process comprises providing an alkaline starch having a pH, when measured in a 20% (w/v) aqueous dispersion, between 9.1 and 11.2, adjusting the water content of the starch to between 2 and 22 wt. %, heating the starch between 130 and 190° C., especially between 140 and 180° C., for a sufficient time and at a sufficient pressure for the inhibition of the starch to be initiated before the water content has reached a level of 1 wt. % and before the pH has reached a value of 9, continuing heating the starch between 140 and 190° C. until viscostability is achieved, and cooling and optionally further processing the starch.