It's the coffee loved by Hollywood and influencers – now researchers say they've found an ingredient that may help explain Kopi Luwak's unique taste.
Kopi Luwak, also known as civet coffee, is made from coffee beans that have passed through the digestive system of the Asian palm civet. The resulting product is not only rare, but also very expensive – around £130 per 500g.
It is also controversial as animal welfare experts raise the issue concern that some producers keep civet cats in autonomous operation conditions.
Now researchers say they have uncovered new clues about coffee's unusual taste by finding that unroasted beans obtained from civet cat droppings have differences in fat content with beans from ripe coffee cherries hand-picked from trees.
“We believe that the fermentation method in [the] gut does[s] Enzymes and microbiome involved in fermentation, said Dr. Palatti Allesh Seenu, co-author of the study from Kerala Central University, India. [in the civet] [are] different from [the] manual fermentation process.
Published in Scientific ReportsSeenu and his colleagues reported how, in January 2025, they collected beans from both wild civet scat and trees on five bean-growing estates in Karnataka, India. Robusta coffee.
The team then prepared and ground both groups of beans, although they did not roast them, before analyzing them.
“When roasting, some heat-sensitive oils and esters can degrade or change their profile,” Sinu said.
Although the team noted that some previous studies found that kopi luwak has less protein and caffeine compared to traditional coffee. right down to the beans passage through the civet's gastrointestinal tract—there were no significant differences in protein or caffeine levels between the two groups of beans analyzed in the new study.
However, the beans from the civet scat had a higher fat content, as well as higher levels of two fatty acid methyl esters, substances based on the building blocks of fats.
The team says the results may help explain the taste of Kopi Luwak.
“Fats and oils are important ingredients in flavors,” Sinu said, noting the many volatile organic compounds—substances that help impart aroma and flavor – use fat as a medium or carrier.
Ramit Mitra, first author of the study, said the two fatty acid-based substances are commonly used in the food industry as flavoring agents and likely impart a milky taste.
“Therefore, we cannot rule out the possibility that these two compounds influence the flavor profile,” he said.
The researchers note that there are other important factors that influence the taste of coffee.
“The core flavor of coffee is formed mainly by roasting and the chemical changes that occur during this process. Our research focuses on the raw form,” Mitra said.
Dr Simon Maher, associate professor of sensors and analytical instrumentation at the University of Liverpool, who was not involved in the work, said the study suggests civet digestion changes the chemical profile of the beans.
“The civet-treated beans showed slight differences, with higher fat content and higher levels of certain fatty acids that may affect flavor, although the study was based on small samples of unroasted beans,” he said.
“Further research is needed to confirm how much of this substance survives roasting and shows up in sensory tests,” he added.
