Xanthan gum is produced by the fermentation of glucose and sucrose. The polysaccharide is prepared by the bacteria being inoculated into a sterile aqueous solution of carbohydrate(s), a source of nitrogen, dipotassium phosphate, and some trace elements. The medium is well-aerated and stirred, and the xanthan polymer is produced extracellularly into the medium. After one to four days, the polymer is precipitated from the medium by the addition of isopropyl alcohol, and the precipitate is dried and milled to give a powder that is readily soluble in water or brine.