The medium is used for the differentiation of Clostridium sulphite reducing. Prepare a suspension of sample analyzed, precipitated solid phase and contribute over sedimentary part of the suspension prepared in sterile medium in test tubes at a temperature of about 70 ° C. the Tubes are incubated at 37 ° C for 24-48 h. Clostridium is capable of recovering the sulfur is converted sodium sulfite (which in high concentration is included in the composition of the medium) to hydrogen sulphite which in turn reacts with the iron ions causing a blackening of the medium.

The analysis is eliminated by aerobic microflora, and part of the vegetative cells that do not stand up to the initial temperature of the medium.