Differences in amylose aggregation and starch gel formation with emulsifiers

The effects of different kinds of emulsifiers, polyglycerol ester and glycerol monostearate, and the surface-active lignosulfonate, on network formation and aggregation of amylose and starch in gels were studied. Pastes with emulsifier and 5% amylose or different starches were heated to between 90 and 150 °C, cooled and studied by means of transmission electron microscopy. ne-stranded amylose network aggregated into thicker strands when emulsifiers were added. At high emulsifier concentrations, spherical aggregates without internal structure formed, and the network disappeared. In wheat starch gels, a lower concentration of emulsifier was needed for amylose aggregation than in pure amylose gels. At high temperatures (>140 °C), aggregation was more ordered, and long, needle-like threads or brush-like aggregates were achieved. The amylose aggregated similarly with the complexing emulsifiers used in this work as with the non-complexing surfactant, which showed that amylose–lipid complex formation was not the primary explanation for aggregation.