Overview
EN ISO 19020:2017 - Microbiology of the food chain - Horizontal method for the immunoenzymatic detection of staphylococcal enterotoxins in foodstuffs - specifies a validated screening method to detect staphylococcal enterotoxins SEA, SEB, SEC (C1–C3), SED and SEE in foods intended for human consumption. The method combines an extraction and concentration step (dialysis-based concentration, mandatory for some matrices such as milk and dairy products) with immunoenzymatic detection using commercially available enzyme immunoassay (EIA) kits. ISO 19020:2017 focuses on practical laboratory procedures, performance criteria and quality control for routine detection of enterotoxins in the food chain.
Key topics and technical requirements
- Scope and targets: Screening for enterotoxins SEA–SEE; applicability to other SE types (SEG, SEH, SEI, SER, SES, SET) only after validation due to lack of commercial kits.
- Two-step method:
- Extraction of toxins from food matrices.
- Concentration (dialysis principle) followed by EIA-based immunoenzymatic detection with commercial kits.
- Matrix considerations: Specific procedures and a mandatory concentration step for milk and dairy products; method evaluated on representative food matrices.
- Performance criteria: Sensitivity (SE), specificity (SP) and limit of detection (LOD) requirements; LOD50 is set with reference to toxicological benchmark dose approaches (BMD/BMDL) to protect consumer health.
- Quality assurance: Requirements for sampling, reagents, apparatus, storage, controls and reporting; guidance on performance verification and interlaboratory study results are included.
- Limitations: Focused on immunoenzymatic kits; alternative analytical approaches (e.g., LC–MS/MS) are mentioned as emerging but are not standardized here.
Applications
- Routine screening of finished food products and ingredients for staphylococcal enterotoxins to support food safety programs.
- Outbreak investigation and public health surveillance where rapid detection of SEA–SEE is required.
- Compliance testing to support regulatory or microbiological criteria within the food industry.
- Method reference for laboratories validating immunoassay kits for specific matrices.
Who should use this standard
- Food and beverage testing laboratories (private and public)
- National and regional public health laboratories and food safety authorities
- Food producers, quality assurance teams and contract testing providers
- Developers and vendors of immunoenzymatic detection kits seeking benchmark performance criteria
Related standards
- ISO 3696 - Water for analytical laboratory use (referenced for reagent quality)
- ISO 7218 - General requirements and guidance for microbiological examinations of food and animal feeding stuffs
Keywords: EN ISO 19020:2017, staphylococcal enterotoxins, immunoenzymatic detection, foodstuffs, screening method, SEA SEB SEC SED SEE, extraction and concentration, food microbiology.