Description
MacConkey Broth is a selective presumptive medium for detecting and enumerating coliform bacteria and Escherichia coli.
Bile salts inhibit much of the accompanying Gram-positive flora, while lactose fermentation produces acid and gas. Acid changes the indicator colour and gas is collected in Durham tubes.
The PDF describes most-probable-number use in water and milk testing. Incubation at the elevated confirmation temperature supports differentiation of Escherichia coli from other coliforms.
