Overview
EN ISO 27107:2010 (identical to ISO 27107:2008, corrected 2009‑05‑15) specifies a potentiometric end‑point method for determining the peroxide value (PV) of animal and vegetable fats and oils. The peroxide value is reported in milliequivalents of active oxygen per kilogram (meq O2/kg) and the method is validated for PVs from 0 meq to 30 meq/kg. The procedure is applicable to fats and oils, fatty acids and their mixtures, and to margarines and fat spreads (including variable water contents). It is explicitly not applicable to milk fats or lecithins.
Key topics and technical requirements
- Analytical principle: liberation of iodine from potassium iodide by peroxides in an acidic medium, with iodine quantified by titration using sodium thiosulfate; the titration end‑point is detected potentiometrically (electrochemical end‑point), not visually.
- Sample mass control: to improve reproducibility, sample masses are fixed (introductory specification: 5 g for PV > 1 and 10 g for PV ≤ 1) - this reduces variability due to sample size.
- Range and limits: validated for PV from 0 to 30 meq/kg.
- Key reagents: degassed glacial acetic acid, isooctane (2,2,4‑trimethylpentane) or solvent mix, potassium iodide (KI), sodium thiosulfate (0.01 N and 0.1 N), and potassium iodate for standardization.
- Apparatus: an automatic titrator capable of dynamic dosing, combined platinum electrode, analytical balance (readability 0.0001 g), volumetric glassware and amber bottles for solution storage.
- Quality considerations: reagents free of dissolved oxygen, freshly prepared/standardized thiosulfate, degassing of solvents, and avoidance of oxidizing/reducing contamination.
Practical applications and users
- Quality control and stability testing in edible oils, vegetable oils processing, animal fats and margarine/fat spread manufacturing.
- Routine testing in food testing laboratories, industrial QC labs, research facilities studying lipid oxidation, and regulatory or certification bodies checking compliance with peroxide limits.
- Useful for shelf‑life assessments, monitoring oxidative rancidity, supplier incoming inspection and process control in oil refining or blending.
Related standards
- ISO 3960 - visual (iodometric) determination of peroxide value (alternative iodometric method).
- ISO 3976 - methods for milk fats (this standard is not applicable to milk fats; see ISO 3976 for those procedures).
- ISO 661 - sample preparation guidance (referenced normative document).
EN ISO 27107:2010 provides a standardized, electrochemical approach to peroxide value measurement, emphasizing reproducibility and traceable titrant standardization - essential for reliable oil quality assessment and compliance testing.
