BS ISO 7251:2005+A1:2023

Microbiology of food and animal feeding stuffs. Horizontal method for the detection and enumeration of presumptive Escherichia coli. Most probable number technique. | Status: Current

1 Scope This International Standard gives general guidelines for the detection and enumeration of presumptive Escherichia coli by means of the liquid-medium culture technique and calculation of the most probable number (MPN) after incubation at 37 °C, then at 44 °C. This International Standard is applicable to

• — products intended for human consumption and the feeding of animals, and
• — environmental samples in the area of food production and food handling.

WARNING — Some pathogenic strains of Escherichia coli do not grow at 44 °C.

A limitation of the applicability of this International Standard is imposed by the susceptibility of the method to a large degree of variability (see Clause 10).