Scientific research

Research paper for Master of Science degree, University of Wisconsin-Stout, WI.

Chocolate liquor is the source of antioxidant flavanols (catechin and epicatechin) and methylxanthines (caffeine and theobromine) found in dark chocolate. Factors that can influence the flavanol and methylxanthine concentration of dark chocolate investigated in this study include the amount of chocolate liquor added, alkalization, and cacao bean genus. The purpose of this study was to quantify flavanols and methylxanthines in different dark chocolates from Legacy Chocolates with different weight percentages of chocolate liquor and different cacao bean genera, Criollo and Forastero. Chocolate samples were analyzed by reverse-phase high performance liquid chromatography (HPLC). Results indicated that the greater the percentage of chocolate liquor added to the final product, the more flavanol antioxidants present. When comparing chocolates with similar weight percentages, the Forastero genus had a significantly greater (p < 0.05) flavanol concentration than the Criollo genus. The Criollo genus resulted in a significantly greater (p < 0.05) caffeine content in dark chocolate when compared to a product prepared with similar weight percentages of chocolate liquor from the Forastero genus. Conversely, the Forastero genus produced a chocolate that was significantly greater (p < 0.05) in theobromine when compared to a Criollo product with similar weight percentages of chocolate liquor. Alkalization processing did not appear to affect catechin, epicatechin, caffeine, or theobromine concentrations in chocolates with similar weight percentages of chocolate liquor. Commercial brand chocolates were analyzed for comparison.

Note: The usage of the terms genus and genera in this abstract is technically incorrect. In fact, there is only one cocoa genus - Theobroma. And there is only one cocoa species - cacao. Forastero and Criollo are widely recognised cocoa cultivars.SM