Overview - ISO 17780:2015 (aliphatic hydrocarbons in vegetable oils)
ISO 17780:2015 defines a standardized laboratory method for the determination of saturated aliphatic hydrocarbons (C10–C56) of natural origin in vegetable oils and for detecting mineral oil and diesel oil contamination. The method applies to all types of crude and refined edible oils and fats and is calibrated for mineral oil concentrations from 50 mg/kg to 1 000 mg/kg. A rapid procedure for refined and virgin (cold‑pressed) oils is provided in Annex C, and a fat‑recovery procedure by Soxhlet extraction for food matrices is given in Annex D.
Key technical topics and requirements
- Analytical principle: isolation of saturated aliphatic hydrocarbons by liquid chromatography on silver nitrate (AgNO3) impregnated silica gel followed by capillary gas chromatography with flame ionization detection (GC‑FID) using an internal standard.
- Target analytes: saturated n‑alkanes and unresolved complex mixture (UCM) from C10 to C56, with diesel indicated by summed n‑alkanes C10–C25.
- Quantification approach: subtraction of naturally occurring sharp n‑alkane peaks from the total hydrocarbon area (including UCM) to estimate mineral oil contribution.
- Reagents & standards: n‑hexane (or equivalent), internal standards (e.g., n‑octadecane or n‑eicosane), alkane mixes (C10–C40), octatetracontane (C48) for integration limits, and AgNO3 for silica gel impregnation.
- Quality controls: procedural blanks, system performance checks, validation of AgNO3‑silica purification, interlaboratory precision data and repeatability/reproducibility criteria are included.
- Annexes: chromatogram examples (A), validation guidance for AgNO3 silica (B), rapid method (C), Soxhlet fat extraction for foods (D), and interlaboratory results (E).
Practical applications and users
Who uses ISO 17780:2015:
- Food and edible oil testing laboratories performing routine quality control and contamination screening.
- Olive oil, rapeseed oil, palm oil and other vegetable oil producers monitoring purity and regulatory compliance.
- Regulatory agencies and public health authorities investigating mineral oil contamination and safety.
- Research laboratories studying oil authenticity, adulteration, or environmental contamination (diesel or mineral oil migration).
Why it matters:
- Enables consistent detection and quantification of mineral oil hydrocarbons and diesel residues in oils and food fats.
- Provides harmonized procedures for comparability of results across labs and jurisdictions.
- Supports contamination incident response, supply‑chain safety, and consumer protection.
Related standards
- ISO 661 - Preparation of test sample (referenced normative document for sample preparation).
- Relevant GC and laboratory quality standards for instrument calibration and method validation.