Water soluble oxidized starches by peroxide reactive extrusion

Oxidation of starches of different amylose content was investigated to increase carboxyl and carbonyl content and to increase water solubility. Three types of 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. Starches with higher amylose content gave reduced solubility, but higher carboxyl content than the low ones. Soluble products had solution viscosities comparable to maltodextrins of dextrose equivalent 5-10. (C) 1997 Elsevier Science B.V.