Thermally-inhibited, pregelatinized non-granular starches and flours are prepared by pregelatinizing the starch or flour and thermally inhibiting the starch or flour by dehydrating the starch or flour to anhydrous or substantially anhydrous and then heat treating the dehydrated starch. The pregelatinization may be carried out prior to or after the thermal inhibition using known methods which disrupt the granular structure such by drum drying or jet cooking and spray-drying. Preferably the starch or flour is adjusted to a pH above 7.0 prior to the thermal inhibition. The starch may be dehydrated by heating the starch in a suitable heating apparatus, by extracting the water from the starch using a solvent such as ethanol, or by freeze drying the starch. Preferably the starch or flour is treated with a solvent to remove proteins and/or lipids and thus prevent off flavors.