An official website of the United States government.

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

Development and Study of Tests to Differentiate Between Tolerant and Sensitive Isolates of Salmonella and Escherichia coli O157

Health Protection Agency
Start date
End date
This research project aims to identify simple, reproducible methods to distinguish between strains of Salmonella and E.coli O157 on the basis of their tolerance to environmental stress.

This study aims to identify simple, reproducible methods to quantify the stress tolerance of different strains of Salmonella and E. coli O157.

Until now, comparison of published data on stress tolerance has been problematic due to differences in the experimental method used, so the effect of different methods on observed tolerance was investigated.

More information
Even within closely related groups of bacteria, variations occur in their ability to survive exposure to environmental stresses, such as acid or high temperature.

Tolerance of stressful conditions is critical for foodborne pathogens such as Salmonella or E. coli, since they may encounter a number of stresses during food processing, preparation or cooking of food by the consumer, and ingestion.

Data generated using highly tolerant strains will help to accurately predict processing conditions that will ensure that no pathogens will survive.

Therefore, it is important to identify the range of tolerance within groups of pathogens, in order to fully assess the risk of the organism surviving and going on to cause infection

Find more about this project and other FSA food safety-related projects at the Food Standards Agency Research webpage.

Funding Source
Food Standards Agency
Project number
Escherichia coli