Cereal Chem. 71:587-593   |  VIEW ARTICLE


Extrusion Processing Conditions for Amylose-Lipid Complexing.

S. Bhatnagar and M. A. Hanna. Copyright 1994 by the American Association of Cereal Chemists, Inc. 

Normal corn starch containing 25% amylose was extruded with and without stearic acid and at various combinations of barrel temperatures, screw speeds, and moisture contents. The presence and amount of starch-stearic acid complexing was measured using iodine binding capacity, apparent amylose content (iodine spectra of soluble fraction of extrudates in 0.5N KOH), and differential scanning calorimetry. Maximum complexing was observed at 110-140 C barrel temperatures, 140 rpm screw speed, and 19% moisture content. Physical properties of extruded starches were also evaluated. The addition of stearic acid before extrusion decreased expansion ratio and water solubility index and increased bulk density.