Overview - ISO 23275-2:2006 (CBE quantification)
ISO 23275-2:2006 specifies a laboratory procedure for the quantification of cocoa butter equivalents (CBEs) in cocoa butter and plain chocolate. The method combines high-resolution capillary gas chromatography (HR‑GC) separation of triacylglycerols (TAGs) with multivariate data evaluation by partial least squares (PLS) regression to estimate the mass fraction of CBEs. The part forms the quantitative element of the ISO 23275 toolbox (with Part 1 covering detection) and is designed to support regulatory compliance such as Directive 2000/36/EC.
Key topics and technical requirements
- Analytical principle: Separation of fat into individual TAG fractions by HR‑GC and prediction of CBE content using PLS regression on selected TAG proportions.
- Calibration & reference material: Use of a certified cocoa butter CRM (IRMM‑801) for system suitability and calibration.
- Fat extraction: Recommended Soxhlet extraction (or validated alternatives) to determine fat content and obtain fat for HR‑GC.
- Chromatography:
- GC with cold on‑column injection (alternatives allowed if validated) and FID.
- Typical column: 25–30 m × 0.25 mm i.d., thermostable 50% phenylmethylpolysiloxane, film 0.10–0.15 µm.
- Example temperature program: 100 °C initial, ramp to 340 °C (program rate cited in standard); carrier gas helium or hydrogen (≥ 99.999%).
- Data evaluation: Partial least squares regression applied to main TAG fractions to quantify CBE down to regulatory levels (method validated for reliable quantification at ~5% CBE).
- Quality and performance: System suitability checks, precision information based on interlaboratory studies (repeatability and reproducibility), and procedural requirements are specified.
Applications and practical value
- Routine laboratory testing for CBE quantification in chocolate and cocoa butter for:
- Regulatory compliance and enforcement (food authorities).
- Quality control in chocolate manufacturing and ingredient verification (R&D and QC labs).
- Supplier certification and traceability of cocoa butter authenticity.
- The method supports consistent, validated quantification that can be integrated into laboratory workflows using CRM calibration and the CoCal‑1 electronic evaluation tools referenced in the standard.
Who should use this standard
- Food testing laboratories and quality control analysts in the chocolate and confectionery industry.
- Regulatory agencies and food safety laboratories performing official controls.
- Instrumentation and method developers validating HR‑GC and chemometric models for fat analysis.
Related standards
- ISO 23275-1 - Detection of presence of CBEs (complements Part 2).
- ISO 5555 - Recommended sampling for cocoa and chocolate (sampling guidance referenced).
- EU Directive 2000/36/EC - Regulatory limits for vegetable fats in chocolate.
Keywords: ISO 23275-2:2006, cocoa butter equivalents, CBE quantification, HR‑GC, triacylglycerols, partial least squares, chocolate testing, food laboratory, IRMM‑801.