Proteome analysis of cocoa beans from diverse geographical origin and linking the variability to final product characteristics (aroma and color)
Cocoa is the bean or fruit that comes from the cacao tree (Theobroma cacao).Cocoa cultivation represents the main source ofincome for thousands of African farmers. The cocoa tree flowers in 2 cycles of 6 months the whole year around and these flowers develop into cocoa fruits.
Figure 1: Cacao tree with cocoa pods
The research program is in the framework of the COMETA cooperation project conducted by Jacobs University Bremen and Barry Callebaut. COMETA project is an interdisciplinary work between four majors namely molecular microbiology, biochemistry, molecular biotechnology and bioinformatics.
My role in the project is to carry out the proteomics study on cocoa beans of diverse origins, qualities and different post-harvest processing. Cocoa proteins will be subjected to sodium dodecyl sulfate and two dimensional protein gel electrophoresis and interesting proteins will be further identified by applying MALDI-TOF and Q-TOF mass spectrometry. Peptide and amino acids strongly contribute to actual chocolate and cocoa aroma upon roasting hence a detail peptide investigation via Capillary-LC and UPLC will be carried out.
Full characterization of the chemical composition of cacao bean will contribute to a more complete understanding in terms of enhancing the taste and aroma of the final product.
Figure 2: Two-dimensional SDS-PAGE of Cocoa bean proteins