Technical Abstract: Oxidation of starches of different amylose content was investigated to maximize carboxyl and carbonyl content, to increase water solubility and to give products with new and novel properties. Three cornstarches containing up to 70% amylose were oxidized by a reactive extrusion-drum drying process, using hydrogen peroxide and a ferrous-cupric sulfate catalyst. Increasing the peroxide level increased oxidation and solubility. Higher amylose content gave reduced solubility but higher carbonyl content. Soluble products had solution viscosities comparable to maltodextrins of dextrose equivalent 5 to 10.