ISO 6888-2:2021/Amd 1:2023

Overview

ISO 6888-2:2021/Amd 1:2023 specifies an internationally recognized horizontal method for the enumeration of coagulase-positive staphylococci, including Staphylococcus aureus and other related species, within the food chain. This amendment updates Part 2 of the standard, which focuses on the technique using rabbit plasma fibrinogen agar medium. It enhances the reliability and accuracy of detecting coagulase-positive staphylococci in food products, particularly fermented foods and those with complex microbial flora.

The method is essential for food safety laboratories and regulatory authorities to monitor and control contamination by Staphylococcus aureus, a pathogen known to cause food poisoning. By using the rabbit plasma fibrinogen agar medium, this standard allows for effective enumeration even in products where other staphylococci species can interfere or where colonies appear atypical on traditional media.

Key Topics

• Coagulase-positive staphylococci enumeration - Accurate counting of Staphylococcus aureus and related species in various food matrices.
• Rabbit plasma fibrinogen agar medium - Utilization of a specialized culture medium that enhances the identification of coagulase-positive colonies.
• Application to complex food flora - Recommended especially for fermented products or raw meat items with competing microbial populations such as Staphylococcus xylosus.
• Method standardization - Guidelines ensure consistency in microbiological testing across international food safety laboratories.
• Measurement uncertainty - Incorporation of ISO 19036:2019 for estimating uncertainty in quantitative test results, ensuring data reliability.
• Amendment updates - Changes to testing protocol and documentation to reinforce clarity and practical applicability, including expanded recommendations for challenging sample types.

Applications

This amendment and the underlying ISO 6888-2 standard serve critical roles in food microbiology, including:

• Food manufacturing quality control - Detecting and quantifying Staphylococcus aureus contamination to maintain hygiene and safety standards.
• Fermented product testing - Applying the method to cheeses made from raw milk, dry-cured meats, and other fermented foods where traditional plating may be inadequate.
• Risk assessment in food safety - Supporting hazard analysis by providing quantitative microbial data essential for monitoring coagulase-positive staphylococci.
• Regulatory compliance - Helping food producers meet legal microbiological criteria by employing internationally validated methods.
• Research and development - Studying staphylococcal behavior in complex ecosystems and developing new food processing or preservation techniques.

Related Standards

• ISO 19036:2019 - Microbiology of the food chain - Estimation of measurement uncertainty for quantitative determinations, referenced for assessing uncertainty in results.
• ISO 6888-1 - Horizontal method for the enumeration of coagulase-positive staphylococci using Baird-Parker agar medium.
• ISO/IEC Directives, Part 1 and 2 - Guidelines followed during the drafting and amendment of ISO 6888-2 to ensure uniform standards development.
• CEN/TC 463 - Collaboration with European Committee for Standardization focusing on microbiology of the food chain.

Keywords: ISO 6888-2:2021/Amd 1:2023, coagulase-positive staphylococci, Staphylococcus aureus, rabbit plasma fibrinogen agar, food microbiology standard, enumeration method, fermented foods testing, food safety, microbiological analysis, measurement uncertainty ISO 19036, microbiology of the food chain.