Coliform bacteria are used often as an indicator of sanitary quality of foods and water.

Coliform bacteria are defined as rod-shaped Gram-negative organisms which ferment lactose with the production of gas when incubated at 35 °C. These organisms are normally found in the aquatic environment and on vegetation. The presence of coliform bacteria in drinking water indicates that the water was not properly treated to eliminate pathogens, or that it became contaminated somewhere in the distribution system.

Escherichia coli (E. coli), a member of the coliform group, can ferment lactose at 44 °C as well. The origin of E. coli is almost exclusively of fecal origin; thus, if it is found in water or food, it indicates fecal contamination, and an imminent health danger, as other fecal pathogens such as viruses or parasites may be also present.

bacteria | Foodborne illnesses

Koliformní bakterie | קוליפורם