Modified starch from maize has been investigated under different pasting conditions. The effect of the time and temperature of gelification, which is known to be of particular importance in the functional properties of starch in industrial processes, has been specifically investigated. The main objective was to evaluate the effect of starch thermal treatment on the rheological properties of a salad dressing, taken as a model of starch-based sauces, and prepared with the same starches in similar pasting conditions. The results obtained are explained on the basis of the relationships among flow behaviour, droplet size distribution and characteristics of the continuous phase.The emulsions became more viscous with increasing starch heating time. The emulsions exhibited a complex viscous behaviour that was fitted to the Carreau model. Flow behaviours of emulsions and starch gels have been compared. A unique master curve has been obtained for all emulsions and gels studied, which depends only on the starch heating time. In addition, changes in microstructure and viscosity, during gelification of the starch dispersion, have been analysed by combining rheological measurements with optical observations and digital image processing techniques.