Plain starch from two varieties of potato and wheat, one variety of rye, triticale, oat, corn, waxy corn, cassava and amaranthus was thermolyzed subsequently at 170, 250, 285, 300 and 325 degrees C for 30 min-2 h intervals. The concentration of unpaired spins was determined. Among varieties studied, the oat starch is least thermally resistant, and both the triticale and maize starches are most thermally resistant. Radicals generated in such a manner are very stable. The analysis of experimental and simulated EPR spectra points to the unpaired spin delocalization and steric hindrances are responsible for the stability of such radicals. (C) 1997 Published by Elsevier Science Ltd.
