Microbiology of food and animal feeding stuffs -- Horizontal method for the enumeration of beta-glucuronidase-positive Escherichia coli -- Part 2: Colony-count technique at 44 degrees C using 5-bromo-4-chloro-3-indolyl beta-D-glucuronide
This part of ISO 16649 specifies a horizontal method for the enumeration of β-glucuronidase-positive Escherichia coli in products intended for human consumption or for the feeding of animals. It uses a colony-count technique at 44 °C on a solid medium containing a chromogenic ingredient for detection of the enzyme β-glucuronidase. WARNING — Strains of Escherichia coli which do not grow at 44 °C and, in particular, those that are β-glucuronidase negative, such as Escherichia coli O157, will not be detected