Microbiology of the food chain - Horizontal method for the enumeration of coagulase-positive staphylococci (Staphylococcus aureus and other species) - Part 1: Method using Baird-Parker agar medium (ISO 6888-1:2021)

2Scope / Description

This document defines a horizontal method for enumerating coagulase-positive Staphylococci on solid medium (Baird–Parker agar) [10] by counting colonies after aerobic incubation at 34 °C to 38 °C and confirming coagulase activity. This document is applicable to—  products intended for human consumption,—  products intended for animal feed,—  environmental samples from food and feed production and handling areas; and—  primary production samples. This horizontal method was originally developed for the analysis of all samples along the food chain. Due to the high variability of products along the food chain, it is possible that this method may not be suitable in all details for every product. However, it is expected that any necessary modifications will be minimized so as not to cause significant deviation from this horizontal method. Based on information available at the time of publication, this method (in whole) is not considered fully suitable for the analysis of fermented products or other products containing a technological flora based on Staphylococcus spp. (e.g., S. xylosus) (such as cheese made from raw milk and certain raw meat products) that are likely contaminated with—  Staphylococci that form atypical colonies on Baird–Parker agar; and—  background microflora that may mask the target colonies. Nevertheless, this document and ISO 6888-2 are accorded equivalent status.