SIST EN ISO 3960:2017 PDF

Overview

EN ISO 3960:2017 - "Animal and vegetable fats and oils - Determination of peroxide value - Iodometric (visual) endpoint determination" is a CEN-endorsed ISO method for measuring the peroxide value (PV) of fats and oils. The standard defines an iodometric titration with a visual (starch) endpoint to quantify peroxides (mainly hydroperoxides) expressed in milliequivalents (meq) of active oxygen per kilogram. It applies to most animal and vegetable fats and oils, fatty acids, margarines and fat spreads with PV from 0 to 30 meq/kg, while excluding milk fats and lecithins.

Key Topics and Requirements

• Scope and applicability: Method valid for fats, oils, fatty acids and mixtures; not suitable for milk-derived fats; PV range 0–30 meq/kg.
• Analytical principle: Liberation of iodine from potassium iodide by peroxides in an acidic medium; iodine titrated with standard sodium thiosulfate using a starch indicator (visual endpoint).
• Solvent system and reagents: Test sample dissolved in a glacial acetic acid/isooctane mixture; reagents must be degassed and free of dissolved oxygen; safety handling required.
• Sample mass control: The PV result is sample-mass dependent. ISO 3960 fixes sample masses (e.g., 5 g when PV > 1 and 10 g when PV ≤ 1) to improve comparability; users should note values may differ slightly from older methods using different sample masses.
• Procedure elements: Includes preparation and standardization (titre determination) of a 0.01 N sodium thiosulfate solution, sampling and test-sample preparation, titration steps, calculation and reporting.
• Quality aspects: Addresses precision (repeatability and reproducibility) and provides guidance on test reporting.

Applications and Users

• Food industry laboratories: Routine quality control of edible oils, fats, margarines and fat-based ingredients to monitor oxidative rancidity.
• Manufacturers and processors: Incoming goods inspection and shelf-life monitoring using peroxide value as an indicator of early oxidation.
• Regulatory and testing laboratories: Compliance testing where peroxide limits are specified in food standards or trade specs.
• Research labs: Comparative studies of oxidation stability or antioxidant performance in lipids.

Practical benefits include a widely accepted, standardized iodometric method for PV that facilitates comparability between labs and supports regulatory compliance and quality assurance.

Related Standards

• ISO 3976 - Preferred iodometric method for milk fats (excluded from ISO 3960).
• ISO 27107 - Potentiometric determination of peroxide value (alternative to visual endpoint).
• ISO 661 - Preparation of test sample for animal and vegetable fats and oils.

Keywords: ISO 3960:2017, peroxide value, iodometric determination, animal and vegetable fats and oils, titration, hydroperoxides, sodium thiosulfate, starch indicator, isooctane, glacial acetic acid.