ISO/PWI 14461

Milk and milk products — Quality control in microbiological laboratories

Scope

ISO 14461 | IDF 169 describes a routine procedure for the evaluation of results of the enumeration of microorganisms using colony-count methods with subsequent 10-fold dilution steps and one plate or two parallel plates within each dilution step.
This routine procedure is applied regularly in each laboratory performing colony counts. It provides criteria for the acceptability of differences between the results from parallel plates and subsequent dilution steps