A study was made of the structure, texture, appearance, colour and consumer sensory analysis of low-sucrose muffins in which the sucrose had been totally or partially replaced (25%, 50%, 75%) by a sucralose:polydextrose mixture (1:1012). The structural characteristics of the muffin batters and of the baked muffins were studied through rheometry, microscopy, image analysis and texture analysis. The replacement of sucrose decreased the viscosity, viscoelasticiy and specific gravity of the raw muffin batter. The evolution of the batter's viscoelastic properties during heating reveals a decrease in the thermosetting temperature with sucrose replacement. These changes in the batter were associated with a muffin with less height, hardness, springiness, cohesiveness, chewiness and resilience and fewer air cells than the control. For 50% sucrose replacement, the appearance, colour, texture, flavour and sweetness and general acceptability were similar to those of the control. Significantly less acceptable muffins were obtained with 100% sucrose replacement.