this disclosure relates to a process for preparing d , l - methionine by feeding carbon dioxide to an aqueous potassium methioninate solution obtained by hydrolysis of 5 - hydantoin , in order to precipitate out crude methionine , which is separated off and purified . in this process an aqueous solution of the separated - off crude methionine is purified by recrystallization from a solution containing potassium ions and also a crystallization additive . the crystallization additive is a nonionic or anionic surfactant , or a mixture of different nonionic or anionic surfactants . the recrystallization occurs by introducing a 60 to 110 ° c .- hot methionine solution into a 35 to 80 ° c .- warm methionine suspension , a temperature of which is lower than that of the introduced solution , such that the temperature of the methionine suspension being maintained between 35 and 80 ° c . during the addition . the crystallization additive is a sorbitan fatty acid ester or a mixture of different sorbitan fatty acid esters .