Macromolecular modifications of manioc starch components by extrusion-cooking with and without lipids

摘要: Abstract Macromolecular structure of manioc starch, extruded without and with lipids (oleic acid, dimodan, soya lecithin copra) was studied, using chemical, enzymic, viscometric chromatographic methods. Twin screw extrusion-cooking led to a macromolecular degradation both amylose amylopectin. The formation lower molecular weight material observed by decrease intrinsic viscosities components also their behaviour on Sepharose CL-2B, whereas no modification β-amylolysis iodine-binding capacity could be detected. increased higher temperature speed the extruder, decreased adding during extrusion. Lipids such as fatty acids, mono- triglycerides have been shown act lubricants (each type in its distinctive way). Lipid extraction, different solvents, appears low efficiency. Although addition extrusion reduces degradation, leading high solubility, amylose-lipid complexes reduce water-soluble fraction. This fraction mainly composed aggregated amylopectin-like highly stable after successive freeze-thaw cycles.