Different types of V amylose-lipid inclusion complexes in maize extrudates revealed by DSC analysis

Aqueous dispersions of the extrudates (1%) prepared from three maize varieties containing starches with the various amylose contents (20-53%) and the high lipid level (about 7% on dry starch weight) were studied by DSC analysis. Two different types of amylose-lipid complexes were observed in the direct process (20-120 degrees C, peak temperature of about 105-107 degrees C) and when reheating/rescanning modes were employed (peak temperature of about 85 degrees C). The extrudate dispersions heated only up to 100 degrees C in the direct DSC scanning modes revealed a double-peaked endothermic profile in the rescans that gave the evidence for coexistence of both types of the complexes. The possible reasons underlying formation, re-formation, and/or coexistence of two types of the amylose-lipid complexes in the maize extrudates studied are discussed.