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As a professor of entomology and plant pathology at the University of Tennessee Institute of Agriculture, DeWayne Shoemaker knows where the magic of Valentine’s Day chocolate boxes truly begins. “I am passionate about chocolate,” says Shoemaker, who has journeyed to the Central American nation of Belize to study cacao.

Tiny gall midges and biting midges, cursed on summer evenings as no-see-ums in the US, are critical for pollinating the flowers of cacao trees. “Cacao flowers are tiny and have complex reproductive structures, so it is likely only smaller insects such as midges can easily access the flower reproductive parts and pollinate them,” said Shoemaker.

From the trees come the seeds or beans, which are shipped around the world and made into chocolate using fairly complex processes. “Ninety-five percent of cacao is grown on small farms,” said Shoemaker. “Fifty million people around the world rely on cacao for their livelihood.”

Shoemaker has twice taught Chocolate—Bean to Bar, an introductory general education course in UT’s Herbert College of Agriculture that covers cacao and how chocolate is produced, shipped, and marketed.

“The students were very enthusiastic,” says Zaklina Pavlovic, a PhD candidate who served as teaching assistant for the more than 100 students who took the class in the fall. “Professor Shoemaker brought samples of different kinds of chocolate for each student, and they liked that. They were also intrigued by the social issues we discussed like slavery and child labor that occur in some areas. It opened their minds to start to wonder, ‘Where does my food come from?’ They were intrigued to hear about workers in the Bahia region of Brazil who introduced a disease called witches’ broom that devastated cacao production in the region. They had wanted to raise the price of their product. Instead, the region’s production will never be the same.”

Professor DeWayne Shoemaker poses with cacao trees.
Professor DeWayne Shoemaker poses with cacao trees.

Now Shoemaker is joining his passions for chocolate and research to create a series of multidisciplinary courses that will take students from the tiny flies to beans, a hands-on chocolate lab, and business studies focusing on the value chain of chocolate companies around the world. “My vision was to create a broad experiential program with cacao as a centerpiece.”

He obtained approval and made plans to take students to Belize in 2020 for the first course in the new program when the pandemic hit. Now planned for next year, the course will include an appreciation for farming cacao trees and the trees’ roles in tropical ecology. It also will incorporate a service–learning project within the community.

In the chocolate lab, students will come to understand the secrets of making chocolate, from roasting the beans to making bars, and creating the different tastes that the world craves. The final course will be a business course on the complex supply chain, from harvesting beans and shipping them around the world to large companies and the final products found in stores.

“I learned a lot more than I expected to,” said Nidhi Menon, a biomedical engineering major, of the introductory class. “We learned about the ins and outs of the chocolate industry—literally from bean to bar. But I was surprised to learn how much the cacao farmers are affected by this industry, thinking of their own income and worrying about potential diseases like black pod rot or witches’ broom that can affect their farms. For the final project, I got to dive deeper into the environmental effects of the cacao industry and see how larger companies are combating environmental issues compared to smaller local ones.”


Patty McDaniels (615-835-4570,

Brooks Clark (865-310-1277,