Overview
EN ISO 12228-1:2014 (ISO 12228-1:2014) specifies a validated gas chromatographic method for the determination of individual and total sterols in animal and vegetable fats and oils. Part 1 covers general fats and oils; olive and olive-pomace oils are handled by ISO 12228-2. The method is endorsed by CEN as EN ISO 12228-1:2014 and is intended for routine and regulatory analysis of sterol composition and content.
Key topics and requirements
- Scope: Quantitative and qualitative determination of sterols (from cholesterol to Δ7-avenasterol) in animal and vegetable fats and oils; results expressed as composition (%) and total sterol content (mg/kg).
- Principle:
- Saponification of a test portion with ethanolic KOH.
- Isolation of unsaponifiable matter by solid-phase extraction on an aluminium oxide column (sterols pass through; fatty acid anions are retained).
- Separation of the sterol fraction by thin-layer chromatography (TLC).
- Conversion to trimethylsilyl (TMS) ethers (silylation) prior to analysis.
- Gas chromatography (GC) for identification and quantification using cholestanol or betulin as internal standards (betulin recommended for hydrogenated oils that may contain cholestanol).
- Reagents & apparatus: Lists analytical-grade solvents (ethanol, diethyl ether), neutral aluminium oxide, TLC plates, silylating reagents, and GC instrumentation. Safety warnings (e.g., diethyl ether peroxide risk) are included.
- Results expression:
- Sterol composition as percentage of total peak area (normalized to 100%).
- Total sterol content in mg/kg of sample.
- Quality: Method includes clauses on sampling, precision (interlaboratory trials), repeatability and reproducibility, and test reporting.
- Normative references: ISO 661 (sample preparation) and ISO 3696 (laboratory water).
Applications and users
- Food and edible-oil testing laboratories performing quality control, authenticity testing, and label compliance.
- Oilseed processors and refiners monitoring product composition.
- Regulatory agencies and standards bodies enforcing compositional requirements.
- Research groups studying lipid composition, nutritional profiling, or adulteration detection.
- Manufacturers of analytical services and GC method developers.
Related standards
- ISO 12228-2 - Sterol determination in olive and olive-pomace oils.
- ISO 661 - Preparation of test sample for fats and oils.
- ISO 3696 - Water for analytical laboratory use.
Keywords: ISO 12228-1, sterols determination, gas chromatography, animal and vegetable fats and oils, unsaponifiable matter, TLC, silylation, cholestanol, betulin, sterol composition, EN ISO 12228-1:2014.