Abstract Sweetness–texture interactions were investigated in model dairy desserts varying in both sucrose concentration and carrageenan composition ( κ-, ι-, λ-carrageenans or an equal-weight mixture of the three). Nineteen panellists evaluated sweetness and five oral texture attributes while instrumental texture was characterised by penetrometry. For each carrageenan composition, sweetness significantly increased with sucrose. Rheological profiles or oral texture attributes allowed to distinguish four matrices. Sweetness–texture interactions were observed but no common rule was applied. On the one hand, firmness of κ-carrageenan desserts, springiness and firmness of ι-carrageenan desserts, unctuousness of λ-carrageenan desserts and brittleness and unctuousness of mix-carrageenan ones increased with sucrose concentration. These changes can be partly attributed to changes in the mechanical profiles. On the other hand, variation of carrageenan composition modified sweetness assessment at higher concentrations, λ-carrageenan desserts being the sweetest and ι-carrageenan desserts the least sweet. A model, which considered carrageenan composition, sucrose concentration and their interactions, was established to relate sweetness and composition of the desserts.