ISO 22174:2005

Overview

ISO 22174:2005 - Microbiology of food and animal feeding stuffs - Polymerase chain reaction (PCR) for the detection of food‑borne pathogens - General requirements and definitions - sets out the baseline requirements and terminology for in vitro amplification of nucleic acids (DNA or RNA) when testing foodstuffs, animal feed and related matrices. Its purpose is to ensure comparable and reproducible PCR results across laboratories by defining general principles, laboratory practices and key terms used in PCR and RT‑PCR for food‑borne pathogen detection.

Key Topics and Requirements

ISO 22174 covers high‑level technical and quality topics without prescribing specific assay recipes. Major areas include:

• Principle and workflow: stages from preliminary enrichment to nucleic acid preparation, PCR amplification, and detection/confirmation of PCR products (endpoint and real‑time).
• Terms and definitions: standardized vocabulary for PCR, RT‑PCR, primers, targets, PCR products, nested/multiplex PCR, hot‑start, master mixes, UNG, thermal cyclers, etc.
• Sample and test material: considerations for food, feed and environmental matrices and isolates.
• Laboratory requirements: layout, personnel competence, contamination control, waste management and biosafety.
• Reagents and equipment: general requirements for reagent quality and special considerations for equipment such as thermal cyclers and real‑time detectors.
• Procedure elements: sample preparation, nucleic acid extraction and purification (PCR‑quality DNA/RT‑quality RNA), amplification protocols, use of controls (positive/negative, process controls) and result confirmation.
• Quality and evaluation: criteria for detection limits, repeatability/reproducibility and result reporting.
• Safety and legal notes: user responsibility for safe handling and awareness of potential patent rights related to PCR technology.

Applications and Who Uses It

ISO 22174 is intended for organizations involved in molecular detection of microorganisms in food and related matrices, including:

• Food and feed testing laboratories
• Public health and regulatory agencies monitoring food‑borne pathogens
• Contract laboratories and quality control teams in food production
• Method developers and diagnostic kit manufacturers
• Accreditation bodies and laboratories seeking compliance with ISO/IEC 17025

Practical benefits include improved inter‑laboratory comparability, clearer method validation, better documentation of procedures and more robust contamination control.

Related Standards

• ISO 20837 - Sample preparation for qualitative detection (complements ISO 22174)
• ISO 20838 - Requirements for amplification and detection for qualitative methods
• ISO/TS 20836 - Performance testing for thermal cyclers
• ISO/IEC 17025 - Competence of testing and calibration laboratories
• ISO 3534‑1, ISO 5725‑1 - Statistical terms and validation principles

ISO 22174 provides the foundational terminology and general requirements that support PCR‑based food microbiology methods, helping laboratories produce reliable, auditable results for food safety decision‑making.