Abstract: Disclosed is a surfactant composition and its use in the production of a gypsum product. Also disclosed is a method of producing gypsum plasterboard, as well as gypsum plasterboard that is formed from foamed slurry comprising the surfactant composition. The surfactant composition comprises from 60 to 99 wt. % by total surfactant weight of an alkyl sulphate component having the structure: R1—OSO3?+M1, in which R1 is an alkyl having from 9 to 11 carbon atoms and M1 is a cation. The surfactant composition also comprises from 1 to 40 wt. % by total surfactant weight of an alkyl ether sulphate component having the structure: R2—(OCH2CH2)yOSO3?+M2, in which R2 is an alkyl having from 8 to 10 carbon atoms, y has an average value of 0.1 to 5 and M2 is a cation.