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Measurement of theobromine content in cocoa for determining cocoa solids content in chocolate and chocolate products - FA0204

EU law lays down rules for the composition and labelling of cocoa and chocolate products and defines different categories of chocolate products including chocolate, milk chocolate, family milk chocolate, white chocolate, filled chocolate etc. Cocoa and chocolate products being sold in the EU have to comply with these rules and must also indicate the minimum cocoa solids content.

Cocoa solids are measured as the sum of cocoa butter and the non-fat cocoa solids component. Determination of the non-fat cocoa solids content is based on measuring the alkaloid markers theobromine and caffeine in chocolate, and using a conversion factor. The conversion factor currently in use was derived over 50 years ago. The aim of the project is to update the conversion factor to take into account the types of cocoa in use today, thus enabling effective enforcement of the regulations.
The objectives of this project were:
• to review and assess the published literature on alkaloid analysis of cocoa and chocolate products
• to collect 200 samples of cocoa from growers around the world and analyse them for levels of alkaloids and fat,
• to carry out a ring trial of methods used by enforcement laboratories and industry for measurement of alkaloids and fat,
• to optimise a method for analysis of alkaloids in the presence of common food additives in chocolate products,
• to measure alkaloids caffeine and theobromine, and fat content in chocolate samples and the liquor from which they were prepared,
• to carry out statistical analysis of the results and determine whether the levels of alkaloids (or theobromine) has changed significantly over time,
• to recommend a conversion factor for calculation of dry fat free cocoa solids from the measurement of alkaloids present in samples,
• to prepare a standard operating procedure (SOP) for analysis of alkaloids in cocoa and chocolate,
• to provide a reference for a method for measurement of cocoa butter in cocoa and chocolate products.
Project Documents
• FRP - Final Report : Measurement of theobromine in cocoa final report   (1003k)
Time-Scale and Cost
From: 2007

To: 2010

Cost: £99,950
Contractor / Funded Organisations
Durham County Council