This standard describes the enumeration of Pseudomonas spp. by colony-count technique, in milk, milk products and environmental samples in the area of dairy production and handling.
The method allows the isolation of all pigmented and non-pigmented psychrotrophic Pseudomonas spp.

This standard cancels and replaces the first edition ISO/TS 11059 | IDF/RM 225: 2009,  which has been revised to include the following minor changes:
— biochemical confirmation tests on oxidase reaction and glucose fermentation test have been aligned with the same confirmation tests used for presumptive Enterobacteriaceae;
— the flow diagram in Annex A giving the main steps of the procedure has been added;
— in Annex B, the criteria for the performance testing of culture media and reagents have been added.