E. coli O157: H7 bacterial species, gram negative, facultative anaerobe, 37 and pH 7,2 at the optimum level of growth, is a bacterium that is mobile and resistant to heat applications.

Two different analysis methods are used to determine the O157: H7 species of Escherichia coli bacteria. A group of analyzes are classical methods of analysis. A group of analyzes are quick methods. Classical analysis methods are carried out by selective enrichment and seeding on solid media. According to the principles of Turkish Food Codex, the presence of E. coli O157: H7 bacteria in foods is investigated in 25 gram sample. The test samples are taken under aseptic conditions and the cold chain is protected and brought to the laboratory.

E. coli O157: Immunological test kits prepared with the principle of immune flow are used for rapid tests for H7 analyzes. The suspension of the colony from the selective enrichment medium culture in water is kept in boiling water for about 15 minutes and then brought to room temperature. Then, a certain amount of this suspension is taken into the kit and placed at room temperature for 20 minutes. A red strip should appear on the kit during this time. This red strip indicates the presence of E. coli O157: H7 in the test sample.

These kits are called rapid kits because they give results in about half an hour after the pre-enrichment step. However, the positive result obtained with this kit is only for escherichia coli O157: H7. H7 antiserum is also required to confirm this bacterial species.

In advanced laboratories, rapid tests for the determination of E. coli O157: H7 are carried out within the framework of microbiological analyzes. During these studies, domestic and foreign standards and analysis methods are taken as basis. The standard received in this regard is dkkate:

• TS EN ISO 16654 Microbiology of food and animal feed - horizontal method for detection of Eschericha coli O157