Overview
EN ISO 23275-2:2008 (identical to ISO 23275-2:2006) defines a laboratory method for the quantification of cocoa butter equivalents (CBEs) in cocoa butter and plain chocolate. The procedure 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 CBE present. The method is intended for routine control and regulatory compliance testing.
Key topics and technical requirements
- Scope and purpose: quantitative determination of CBEs in cocoa butter and plain chocolate; designed to meet statutory limits (method provides reliable quantification at the 5 % level per Directive 2000/36/EC).
- Analytical principle: separation of fat into individual TAG fractions by HR‑GC (according to molecular mass and unsaturation), followed by PLS regression applied to the relative proportions of the main TAGs to calculate CBE content.
- Calibration and reference material: use of a certified cocoa butter CRM (IRMM‑801) for calibration and system suitability checks.
- Reagents and apparatus: non‑chlorinated fat solvents (e.g., diethyl ether, n‑heptane), hydrochloric acid, analytical balance (0.1 mg), drying oven (55 °C), GC with cold on‑column injection and flame ionization detector (FID) or suitable alternative injection systems.
- Procedure elements: fat extraction from samples, HR‑GC separation and identification of TAGs, determination of response factors, calculation of TAG percentages, and computation of CBE content for both cocoa butter and chocolate.
- Quality requirements: system suitability testing, precision assessment (interlaboratory testing, repeatability, reproducibility) and full test reporting requirements.
Applications and users
- Food testing laboratories performing routine quality control and verification of chocolate and cocoa butter composition.
- Chocolate manufacturers and ingredient suppliers monitoring raw materials and finished products for compliance with labelling and legal limits on CBEs.
- Regulatory and enforcement laboratories assessing compliance with food legislation (e.g., EU Directive 2000/36/EC).
- Research and development teams studying fat blends, formulation changes, or authentication of cocoa butter.
Related standards and documents
- ISO 23275-1 - Detection of cocoa butter equivalents (complements Part 2; Part 1 is more sensitive for presence/absence detection down to ~0.6 % in certain matrices).
- Directive 2000/36/EC (EU) - Legal framework governing use and labelling of vegetable fats in chocolate products.
- EN ISO 23275-2:2008 - European adoption of ISO 23275-2 by CEN (for use across member states).
This standard is essential for accurate, legally defensible quantification of CBEs using HR‑GC and PLS regression-key techniques for food analysts, quality assurance professionals, and regulatory bodies in the chocolate industry.