The Chocolate Project :
Chocolate is one of the world's most popular foods, but little is known of the finer details that are involved in the production and quality of this product. Chocolate in itself is very complex because its aroma, flavor, and texture could depend on geographical origin of the cacao bean, vegetation that grows near the cacao tree, type of cacao bean, amount of cacao, conching, added flavors, etc. All of these factors result in products with claims of how their specific brand or bar is more unique than the next, creating a price gradient that separates gourmet chocolate from generic chocolate. The purpose of this study is to use simple chemical tests to differentiate between a wide variety of chocolates in order to determine if there is a specific pattern to characterize chocolate based on brand, price, nutritional content, cocoa content, geographical origin, etc.
The first test was infrared spectroscopy (IR), which required no physical alteration to the samples. In order to ascertain differences among the gathered IR spectra, a continuous wavelet transform was used to distinguish peaks that were both noticeable and consistent so that comparison could be drawn between samples. Continuous wavelet transform showed that the IR peaks that lie in the 3600 cm-1 to 3100 cm-1 region were consistently identified – this region conveniently happened to be an area where the spectral amplitudes showed the greatest variance. Due to this region's consistent detection yet varying nature, it was the optimal region to base all further analysis on.
The second test used high-performance liquid chromatography (HPLC) to quantify theobromine and caffeine in chocolate samples in order to verify the cocoa content that is advertised on many chocolate bar labels. The HPLC tests are currently inconclusive, but the overall goal is to establish a linear relationship between theobromine, caffeine, and cocoa content before the tests can be compared to the claims on the label.
Team Members:Ruben Savizky
Funder/Sponsor/Partner: Science House