Preparation and characterization of aqueous dispersions of high amylose starch and conjugated linoleic acid complex

•CLA was homogeneously dispersed in amylomaize starch solution by simple blending.•V-amylose complex of CLA was prepared in aqueous batch mode.•Complex yield of CLA could reach 67% by thermal control of reaction.•Ultrasonication of the dispersion may improve storage stability. Crystalline starch-CLA complexes were prepared by blending an alcoholic solution of conjugated linoleic acid (CLA) in an aqueous high-amylose maize starch dispersion. Recovery yield of CLA in the precipitates obtained by centrifuging the dispersion was dependent on reaction conditions such as temperature, time and pH. The CLA recovery reached a maximum when the reaction was performed at 90°C for 6h at neutral pH, with 67.7% of the initial CLA being co-precipitated with starch. The precipitates contained amylose-CLA complex exhibiting a V6I-type crystalline structure under X-ray diffraction analysis and a type II polymorph under DSC analysis. Ultrasonic treatment for the re-dispersed starch-CLA complex in water resulted in the reduction of hydrodynamic diameter of the complex particles to 201.5nm. The dispersion exhibited a zeta potential of −27.0mV and remained stable in an ambient storage without forming precipitates for more than 4weeks.