This invention relates to a method for producing a sweetener salt of formula APMH.sup.+Ace.sup.-, according to which aspartame or an aspartame derivative is reacted with acesulfamic acid in a solvent selected among one or several of the following: liquid SO.sub.2; halogenated aliphatic hydrocarbons; carbonic acid esters comprising low, aliphatic alcohols; nitroalkanes; alkyl-substituted pyridines; and aliphatic sulfones. The invention also relates to the use of said sweetener salts in food, beverages, pharmaceuticals, and cosmetics.