Shiga toxin-producing Escherichia coli (STEC) are important foodborne pathogens associated with gastrointestinal illness and serious complications, including hemolytic uremic syndrome (HUS). Among them, E. coli O157 is a well-known cause of foodborne outbreaks. Non-O157 STEC serogroups also present significant food safety concerns, particularly in meat, fresh produce, and other foods vulnerable to contamination.

Coliform testing helps assess drinking-water quality, identify potential contamination, and evaluate hygienic conditions in food processing. US laboratories use EPA-approved analytical methods for regulated drinking water and appropriate FDA, USDA, or validated methods for food, depending on the sample and testing objective.

Reliable detection of Salmonella in food begins with selecting an appropriate enrichment broth. Because the organism may be present in low numbers or can be injured by food processing, enrichment helps recover target cells before selective isolation and confirmation.

Indicator organisms are microorganisms used to assess food hygiene, sanitation practices and the microbiological quality of food products. Their presence or numbers can help identify inadequate processing, post-process contamination or conditions that may support microbial growth. However, indicator results must be interpreted in context because they do not necessarily confirm the presence or absence of a specific foodborne pathogen.

Listeria environmental monitoring is an important part of food safety programs, particularly in facilities manufacturing ready-to-eat (RTE) foods. It involves collecting samples from food-processing environments to detecting Listeria species or Listeria monocytogenes before contamination can affect finished products.

The detection of Listeria monocytogenes in food and environmental samples is an important part of microbiological quality and food safety testing. Selective agar media help laboratories recover presumptive Listeria colonies while suppressing competing microorganisms. However, not all selective media distinguish L. monocytogenes from other Listeria species.

Escherichia coli O157 is a Shiga toxin-producing E. coli (STEC) serotype associated with foodborne illness. Its detection in food and environmental samples is an important part of microbiological food safety testing. Selective and differential agar media help laboratories recover presumptive target colonies from samples that may contain a diverse background of microorganisms.