Department COVID-19 Updates:
COVID-19 Research Planning

Researchers from Nebraska, Ethiopia rethinking the coffee ‘cherry’

Food Science

Jim Benes, October 22, 2021

Researchers from Nebraska, Ethiopia rethinking the coffee ‘cherry’

Starting the day with a cup of coffee is a daily ritual for many across the United States, and variations on coffee have changed over time, including the trendy options — iced, frozen, cold brew — and of course, the traditional hot and black.

It turns out the habitual infusion, no matter how you drink it, has research connections with the University of Nebraska–Lincoln. Those connections start where the coffee is grown, a world away from the Great Plains of North America.

Coffea arabica is indigenous to Ethiopia and the country remains one of the world’s leading bean producers. The production chain from coffee plant to roaster to the morning cup is a long one, with discharge of useful byproducts at every turn.

It starts with the coffee bean, which needs a little context. The coffee “bean” is not a bean at all, but one of two seeds from a fruit, or cherry. Once the bean is extracted, the rest of the fruit is discarded as waste, leading to environmental degradation and other hazards at processing sites, typically near water. Already, coffee farmers are under intense pressure from the risks imposed by anthropogenic climate change, so a new source of revenue would be a welcome option for many in the region.

Mary Willis, professor of nutrition and health sciences in the College of Education and Human Sciences, and Curt Weller, chair of Food Sciences and Technology at IANR, along with colleagues from Hawassa University, Hawassa, Ethiopia, are working to tackle this challenge.

The Hawassa faculty, Fikadu Reta Alemayehu and Alazar Kirubel Kora, visited Nebraska in both winter and summer over the last year.

Researchers (from left) Aemiro Tadesse Zula, Alazar Kirubel Kora, Fikadu Reta Alemayehu and Mary Willis have been working together on finding ways to repurpose the cherry waste that comes from harvesting coffee beans. Loren Rye/Pixel Lab

Researchers (from left) Aemiro Tadesse Zula, Alazar Kirubel Kora, Fikadu Reta Alemayehu and Mary Willis have been working together on finding ways to repurpose the cherry waste that comes from harvesting coffee beans. Loren Rye | Pixel Lab

During the summer visit, they brought along another colleague, Aemiro Tadesse Zula, to work with Richard Zbasnik, a food science research technologist, at Innovation Campus on the composition of cherry waste.

The discarded cherries have tremendous nutritional value and could be an important source of economic gain for coffee farmers who ensure that coffee beans are available. Repurposing coffee cherry processing waste means that some of the micronutrients and trace minerals missing from the diets of many Ethiopians, including vitamin A, iron, zinc and potassium, can be provided to communities in need, perhaps in a new supplement or product.

Willis and her colleagues are addressing these issues head on in a variety of ways. The team has several manuscripts in the works, including a review paper on the status of coffee-cherry byproducts worldwide. They delivered an online workshop titled, “Waste Not, Want Not: Repurposing Coffee Cherries to Improve the Livelihoods of Growers in Southern Ethiopia.” The workshop had approximately 100 participants from across the global community, including stakeholders and researchers in Lincoln, Nebraska; Addis Ababa, Arba Minch; Hawassa, Ethiopia; England; and Germany.

Willis was pleased with the international scope of the attendees at the workshop noting that the breadth of interest in the topic reveals a commitment to improving the lives of coffee growers and at the same time, reversing unnecessary environmental damage.

This research also bolsters the university’s International Strategic Plan, Forward Together. Specifically, Goal 2 — Partner for Impact: Support and incentivize contributions toward solving global grand challenges through strategic partnerships. The plan calls to align with the Grand Challenges and to adopt the United Nations Sustainable Development Goals — both advancements are accomplished by addressing climate change resilience of local coffee farmers, and improving waste streams for improved water security and food sustainability.

The continuing research was made possible through the University of Nebraska system’s African Research Initiative.

To learn more about the global work in the coffee supply network at Nebraska, email Mary Willis at mwillis2@unl.edu.


Food Science Nutrition and Health Sciences