The oxidation of starches of different amylose content with several ox
idants has been investigated to maximize carboxyl content, increase wa
ter solubility and give products with new and novel properties. Method
s of preparation studied were ambient-batch, jet cooking, jet cooking-
drum drying, and drum drying alone. Other variables evaluated were rea
ction pH, jet cooking temperature, and oxidant concentration. Hypochlo
rite was the most effective oxidant and gave the highest carboxyl cont
ent in all preparation methods. Oxidized starches prepared by jet cook
ing and/or drum drying were of low viscosity and water soluble. SEM's
of commercial oxidized starch showed intact granular structure, wherea
s samples prepared by instantaneous high temperature procedures showed
complete gelatinization. Gel permeation chromatography showed structu
ral depolymerization of the starches when high temperature processing
was used. Copper binding capacity was evaluated on selected samples.