IRES Track I: The Broad Impact of Flavor. A Research Experience on Metabolomics of Microbial Populations during Cacao Fermentation at the Escuela Superior Politecnica de Litoral

Centered on the development of the complex flavor profile of fine flavor cacao during fermentation, this IRES aims at enhancing the global and scientific competency of the student participants. This program promotes the participation of minorities and underrepresented students in STEM disciplines. The craft chocolate industry has grown rapidly over the last decade in the US and other parts of the world.

The global trade of fermented and dried cocoa beans affects the lives of millions of individuals from cacao growers to chocolate manufacturers and the consumer. About 5% of the cacao produced in the world is from varieties that produce high quality chocolate, with Ecuador as one of the largest producers of such varieties. However, the large variability in the quality of fermented beans affects the quality, acceptability, and value of the chocolate produced.

The variability in the quality of fermented cacao also lowers the price that local cacao growers, mostly smallholders, are paid. Despite its impact on flavor, of all the stages of chocolate production, cacao fermentation remains the most complex and the least studied. In this IRES project, U.S. students will participate in multidisciplinary research to better understand and control the variability of cacao fermentation in Ecuador.

Students will learn research methods, experiment design, chemical analysis, food microbiology, sensory analysis, and multivariate data analysis. Every year, for three years, cohorts of two graduate and two undergraduate students from across the U.S. will be immersed for 8 weeks in a diverse team in Guayaquil, Ecuador. Students will be mentored by cross-disciplinary faculty from the University of Georgia, and from the Center for Biotechnology Research of Ecuador (CBRE), as well as by the quality manager at KAOKA, a French chocolate manufacturer with fermentation operations in Ecuador.

In this international industry-academia collaboration, students will participate in laboratory and field research where they will further their scientific, professional, and sociocultural skills.

Our research goal is to consistently produce high-quality cocoa products through controlled fermentations. Students from each cohort will work on one of five subthemes that aim at characterizing the sources of variability, harnessing them, and designing systems and procedures that minimize variability. Research activities with scientific mentors and local students at CBRE include analyzing the chemical composition of fresh cocoa beans using a metabolomics approach that encompasses advanced chromatographic methods and multivariate analysis.

This approach will help elucidating the variability of the raw material and correlating the principal components to the quality of the fermented beans. At KAOKA, students will learn the daily operation of a large fermentation facility and interact with technical staff and workers to design and execute field experiments. Students will characterize the chemical composition and analyze the evolution of the microbial populations to identify means of measuring and controlling the progress of the fermentation.

Students will also analyze the composition of chocolate produced from different fermentation batches to assess how composition affects the flavor complexity and the duration of the organoleptic experience and strategize means of producing the best quality attributes. Finally, informed by all the previous studies, some of the participants will design and optimize a small-scale fermenter for smallholders.

The dissemination of this IRES is expected to inspire other students from minorities and underrepresented groups to pursue STEM careers and participate in similar experiences. This research is expected to benefit the growing U.S. craft chocolate industry and contribute to eventually help cacao smallholders and their communities. This new knowledge likely to positively impact the fermentation of other cacao cultivars in other regions and to contribute to the U.S. leadership in science-driven development efforts in developing countries.

This project is jointly funded by the International Research Experiences for Students program (IRES) and the Division of Biological Infrastructure.

This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.