Overview
ISO 27608:2010 specifies an automatic method for determining Lovibond® colour of animal and vegetable fats and oils. The standard defines how to measure transmitted colour using automatic colorimeters and express results in Lovibond units, with guidance on instrumentation, sample preparation, measurement procedure, and reporting. It was developed to provide repeatable, reproducible automated measurements that align with the traditional manual Lovibond scale within practical limits.
Key topics and requirements
- Scope: Applies to automatic instrumentation for Lovibond colour measurement of fats and oils. Not suitable for samples with Lovibond red > 4 units or those with strong blue, green or brown hues; for such samples use the manual reference method (ISO 15305).
- Apparatus: Automatic colorimeter with spectral response 400–700 nm reporting results in Lovibond units. Examples of suitable instruments are listed in the standard (trade names provided for convenience).
- Reference standards & calibration: Use certified glass or liquid reference standards for calibration and routine verification to support quality systems (ISO/IEC 17025, ISO 9000).
- Optical path lengths: Standard cell path lengths include 1.6 mm, 3.2 mm, 6.4 mm, 12.7 mm, 25.4 mm, 76.2 mm, and 133.4 mm; choose path length to match sample colour saturation.
- Sample preparation: Prepare according to ISO 661; samples must be liquid, clear and free of turbidity. Heat solids to ~10 °C above melting point (avoid scorching). Filter to remove turbidity; filtration must not alter colour.
- Procedure highlights: Stabilize instrument, select Lovibond scale and path length, perform baseline calibration, verify with reference standard, control sample temperature, insert correctly filled cell, obtain Lovibond readings from the display.
- Results & reporting: Report Lovibond values and the optical path length used. Include sample ID, apparatus details, preparation notes, measurement temperature and reference to ISO 27608:2010.
- Precision: Precision (repeatability and reproducibility) was evaluated in interlaboratory trials (Annex A); results and limits are provided there and derived per ISO 5725.
Applications and users
- Quality control and QA in edible oil, fat processing and refining
- Food testing laboratories and contract analytical labs
- Incoming goods inspection for manufacturers using animal and vegetable fats/oils
- Instrument manufacturers and calibration/service providers
- Regulatory and standards bodies assessing colour specifications in trade contracts
ISO 27608:2010 helps organizations implement reliable, automated Lovibond colour measurement for routine quality assessment, traceable calibration, and consistent reporting across laboratories.
Related standards
- ISO 15305 - Manual Lovibond colour method (reference manual method)
- ISO 661 - Preparation of test sample (sample preparation)
- ISO 5555 - Recommended sampling (sampling guidance)
- ISO 5725 - Precision of measurement methods (statistical analysis)