A gypsum composition including gypsum, water, and a surfactant composition of alkyl sulfates of formula H(CH₂)_nOSO₃^-M⁺, in which n is from 6 to 16, the mean number of carbon atoms in the alkyl sulfate composition n_m being between 10 and 11, and M is a monovalent cation. A process for the preparation of the gypsum composition and a gypsum board obtainable from this composition. Finally, a process for the manufacture of gypsum boards. Application for the manufacture of foamed gypsum boards.