A simple selective and differentiating synthetic medium (X broth) that is easy to prepare was developed in liquid form for the
selective cultivation of coliform bacteria from foodstuffs. This synthetic medium contains an ammonium salt as nitrogen source,
lactose as carbon source, and buffers but is free of inhibitors. Its selectivity is based on the fact that coliform bacteria are able to
grow ifthe minimal medium consists ofsimple inorganic substances as nitrogen sources and lactose as carbon supply