Validation by interlaboratory trials of EN ISO 10272 - Microbiology of the food chain - Horizontal method for detection and enumeration of Campylobacter spp. - Part 2: Colony-count technique

Abstract

The validation in an interlaboratory study of the International Standards Organization standard method for the enumeration of Campylobacter in foods (ISO 10272-2) was performed after preparation of the revised Standard based on scientifically sound and validated methods of analysis.The matrices selected for testing in the collaborative trial were frozen spinach, minced meat, raw milk, chicken skin, and broiler caecal material. Each matrix was artificially inoculated with a different Campylobacter strain. Fifteen laboratories participated in the interlaboratory study.As a general indication of repeatability limit (r), the following overall values can be used when testing chicken skin samples:r = 0.98 (expressed as a difference between log10-transformed test results), orr = 9.52 (expressed as a ratio between test results).As a general indication of reproducibility limit (R), the following overall values can be used when testing chicken skin samples:R = 1.31 (expressed as a difference between log10-transformed test results), orR = 20.43 (expressed as a ratio between test results).The validation data for all matrices were incorporated in the newly published ISO standard EN ISO 10272-2:2017 - Microbiology of the food chain - Horizontal method for detection and enumeration of Campylobacter - Part 2: colony-count technique.