Muller Kauffmann Broth Base is a recommended selective broth for isolating Salmonella from animal faeces, polluted sewage water, food, milk, ice cream and pasteurized egg-base products. Using more than one selective broth increases the isolation of Salmonella from samples with multiple sera types. It is also recommended to use Tetrathionate Broth (Cat. Cl-1114) for the isolation of Salmonella.

Kauffmann modified the formula to include ox bile and brilliant green as selective agents to inhibit Gram-positive microorganisms. Sodium thiosulfate plus iodine result in tetrathionate formation, inhibiting coliforms and intestinal bacteria. Acidic tetrathionate decomposition products such as sulphuric acid is formed, which are neutralized by calcium carbonate, acting as a buffer. Salmonella and Proteus are not inhibited as they reduce tetrathionate. Meat peptone, beef and yeast extracts provide nitrogen, vitamins, minerals, and amino acids essential for growth. Sodium chloride supplies essential electrolytes for transport and osmotic balance.

Iodine Solution:

• Potassium Iodide: 25 g


• Iodine: 20 g


• Distilled Water: 100 ml

Dissolve the potassium iodide in 5 ml of distilled water, add the iodine and gently warm the solution to dissolve completely. Make the volume reach 100 ml with distilled water.

Brilliant Green Solution:

• Brilliant Green: 0,1 g


• Distilled Water: 100 ml

Add the brilliant green to the distilled water, shake and heat at 100ºC for 30 minutes to ensure the dye has dissolved. Store in brown bottles.