Overview
EN ISO 18363-1:2021 (ISO 18363-1:2015) specifies a GC/MS method for the indirect determination of fatty-acid‑bound chloropropanediols (MCPDs) and glycidol in animal and vegetable fats and oils. The method uses a fast alkaline transesterification, followed by derivatization (phenylboronic acid, PBA) and gas chromatography–mass spectrometry (GC/MS) analysis. It enables measurement of 3‑MCPD esters and a differential determination of glycidol (by converting glycidol to induced 3‑MCPD under controlled conditions). Milk and milk‑derived fats are excluded from the scope. The standard is published by CEN as EN ISO 18363‑1:2021 and is identical to ISO 18363‑1:2015.
Key topics and technical requirements
- Analytes covered: ester‑bound 3‑MCPD and glycidyl esters (glycidol), including possible free 3‑MCPD present in samples.
- Analytical principle: fast alkaline catalysed alcoholysis at room temperature to release bound analytes, PBA derivatization and GC/MS detection.
- Differential approach: two assays (A and B) -
- Part A converts glycidol to 3‑MCPD using an acidified chloride solution so 3‑MCPD + induced 3‑MCPD are measured together.
- Part B uses a chloride‑free stop solution to measure genuine 3‑MCPD only. Glycidol concentration is calculated from the difference (A − B) using a determined transformation ratio.
- Scope limits & assumptions: Applicable to solid and liquid fats and oils (refined and non‑refined); excludes milk/milk products. Indirect glycidyl ester determination assumes no other sample components react with chloride at room temperature to produce 3‑MCPD.
- Method structure: reagent specifications, apparatus, sampling/preparation, spiking with surrogate standards, ester cleavage, matrix cleanup, derivatization, GC/MS conditions, expression of results, and precision (interlaboratory, repeatability, reproducibility).
Applications and users
- Food safety and regulatory testing: routine monitoring of 3‑MCPD and glycidol in edible oils and fats to meet regulatory limits and risk assessments.
- Industrial quality control: refining plants, oil processors and frying‑oil users monitoring process steps that can generate MCPDs/glycidol.
- Analytical and research laboratories: method implementation for surveillance, method validation, and interlaboratory studies.
- Who should use it: QC chemists, food control authorities, contract testing labs, and researchers working on contaminants in fats and oils.
Related standards
- EN ISO 18363 series (other parts cover alternative transesterification and measurement approaches).
- The method is equivalent to DGF standard C‑VI 18 (10) and identical to AOCS Official Method Cd 29c‑13 (as noted in the ISO introduction).
Keywords: EN ISO 18363-1:2021, ISO 18363-1:2015, 3‑MCPD, glycidol, glycidyl esters, MCPD esters, GC/MS, alkaline transesterification, animal and vegetable fats and oils, food safety testing.