Coliforms – Traditional hygienic indicator
Recently, local media reported that edible ice cubes obtained from food premises was detected to be contaminated with coliforms. The media has raised the concerns whether those edible ice samples had been contaminated with faecal matter. The following paragraphs provide the answers to some of the commonly asked questions regarding coliforms.
What are coliforms?
Coliforms are not a single species of organism. They are a group of closely related, mostly harmless bacteria that live in soil and water as well as the gut of animals. Coliforms count is a hygienic indicator and high level of coliform counts generally indicates unsanitary condition or poor hygiene practices during or after food production.
Is the presence of coliforms in food a direct evidence of faecal contamination?
It must be stressed that some members of coliforms are present as normal inhabitants in the environment, e.g., soil, vegetation and water. Testing for total coliform is not intended to detect faecal contamination, but rather to reflect general hygiene during food production or handling and the quality of the measures used to minimise bacterial contamination.
Does the presence of coliforms in food indicate the presence of pathogens?
The presence of coliforms does not necessarily mean that pathogens are present. While the detection of pathogens in ready-to-eat food indicates a risk of foodborne illness, the level of coliforms only reflects the general hygienic conditions during food production or handling.