Quality Parameters, Caffeine and Theobromine Contents and Antioxidant Activity of Artisan and Commercial Chocolate from Brazil

Abstract

Several types of chocolate were analysed: bitter, half-bitter, milk chocolate, 70% cocoa, white chocolate and cocoa seeds. Analysis of fat, insoluble solids, total phenols, theobromine and caffeine contents and antioxidant capacity were carried out to evaluate the quality of artisan and commercial chocolate products in Brazil. Fat contents and insoluble residues were similar to those reported in the literature. We develop a simple method by HPLC-DAD (High-Performance Liquid Chromatography with Diode-Array Detection) to quantify methylxanthines whose identification has been confirmed by UPLC- MS (Ultra performance liquid chromatography—mass spectrometer). The levels of phenols, caffeine and theobromine varied between types. White chocolate had no phenolics nor caffeine or theobromine. The ones with the highest phenolic contents were those with the highest cocoa mass content. The same happened with the antioxidant activity, which is correlated to the amount of phenolics, caffeine and theobromine, shown by the statistical analysis. It is the presence of cocoa that determines the antioxidant activity of chocolates. This work contributed to the confirmation of the properties of the chocolates, highlighting the importance of the artisan product. Chocolates are important for human health and are considered functional foods.