Brewing sustainability in Yemeni coffee
When we think of Yemen, we often think of its ancient history or, more recently, the devastating humanitarian crisis. But on the steep terraces of its western highlands, a different story is brewing. Amid Yemen’s challenges, a study by Utrecht University shows that specialty coffee cultivation has significant potential for positive impacts on thousands of smallholder farmers. With the help of trade models like Seed-to-Cup, where buyers work and buy directly from farmers, Yemeni coffee can become both more sustainable and profitable.
The study, led by researchers from the Copernicus Institute of Sustainable Development, is a collaboration with Qima Coffee, an international ethical coffee sourcing, marketing, and development organization, analysed the environmental cost of a cup of Yemeni coffee, from the moment the seed is planted to the moment it reaches the importer's warehouse in the UK. Using Life Cycle Assessment (LCA), the researchers reveal that producing 1 kg of these green coffee beans carries a carbon footprint of 3.14 kg CO2 equivalent. This total carbon footprint includes activities of coffee cultivation, processing, and international transport to the UK, while excluding the roasting of coffee beans, the use, and the disposal phases. While the footprint itself is low compared to other coffees, the research found that over 90% of emissions happen during cultivation. This means that leverage points for improving the sustainability of Yemen's coffee it lies in what happens on the farm.
Why Yemen’s coffee has a surprisingly low footprint
On the one hand, smallholder Yemeni coffee production has environmental advantages. Farmers use a traditional dry-processing method that requires zero water. The harvested cherries are dried in the sun on the rooftops of houses or on raised beds. This method does not require water for pulping or fermentation, avoiding the massive water waste common in other coffee-producing regions.
Why low yields matter
It all comes down to the yield gap - the difference between how much could be produced under good conditions and how much is actually produced. Coffee trees in Yemen produce few cherries due to water scarcity and the ongoing regional conflict that have led to a lack of workforce limited resources. As a result, inputs such as chemical fertilisers are spread across smaller harvests, increasing the environmental footprint per kilogram of coffee. "By increasing the harvest of each tree, we can spread the environmental cost of cultivation across a larger volume of coffee, mathematically slashing the footprint of each cup,” says lead author Larissa van der Feen.
Strengthening value chains to improve sustainability
Improving cultivation and fertilization practices is therefore essential for increasing harvests and making Yemeni coffee both more sustainable and profitable. “Strengthening high-proximity value chain models like the Seed-to-Cup, where one market agent covers the entire supply chain from coffee cultivation to distribution and roasting, is key here,” says Van der Feen.
High-quality specialty coffee requires significant knowledge and skills to be both sustainable and profitable. Among other things, high-proximity value chain models can first-hand identify and respond to community needs, guarantee a minimum price and upfront payments for producers that cover production costs and enable investments, and foster the mutual trust needed for farmers to adopt sustainable practices, ensuring a coffee value chain that is as resilient as it is environmentally efficient. “Empowering farmers in this way does more than improve livelihoods; it creates the conditions needed to reduce the environmental impact of coffee at its source,” says Van der Feen.
Publication
van der Feen, L., Verweij, P. A., Vermeulen, W. J., Montagnon, C., & Sheibani, F. (2025). Life cycle assessment of Seed-to-Cup specialty coffee cultivated by smallholders in Yemen. The International Journal of Life Cycle Assessment, 30(8), 1761-1775.