Interlaboratory Proficiency Tests for the Detection of Cronobacter and Salmonella in Milk Powder

The contamination of milk powder by pathogens such as Cronobacter and Salmonella represents a major public health risk, particularly as the primary consumers of milk powder, infants, have heightened vulnerability to bacterial infection. In the face of this danger, analytical laboratories must implement and practice methods for the detection of these microorganisms with high accuracy. For this reason, BIPEA (Bureau Interprofessionel d’Études Analytiques) launched a new proficiency testing program for the detection of Cronobacter and Salmonella in samples of milk powder in 2019.This paper presents the design and implementation of the program, as well as a detailed analysis of laboratory results and systems for the evaluation of qualitative proficiency testing performances. Results from these tests are encouraging, as the majority of laboratories are able to correctly identify both contaminated and uncontaminated samples. These tests are an essential quality control tool for laboratories to assess and demonstrate their competence to carry out these microbiological analyses, which are critical for public health, and to comply with the requirements of the ISO/IEC 17025 standard.