Scientists from the Institute of Science Tokyo have uncovered the science behind the exceptionally smooth taste of Black Ivory coffee, one of the rarest and most expensive coffees in the world. Their research reveals that gut bacteria in Asian elephants play a crucial role in reducing bitterness and enhancing the coffee’s distinctive flavour.
Black Ivory coffee is produced exclusively at a single elephant sanctuary in Thailand, where elephants are fed Arabica coffee cherries. After the cherries pass through the elephants’ digestive systems, the beans are collected from the dung, thoroughly cleaned, and then roasted. The result is a coffee prized for its mild, chocolaty notes and low bitterness.
How Elephant Digestion Changes Coffee Chemistry
To understand what makes Black Ivory coffee different, researchers analysed dung samples from elephants that consumed coffee cherries and compared them with samples from elephants at the same sanctuary that did not.
They discovered that elephants producing Black Ivory coffee had high concentrations of gut bacteria capable of breaking down pectin, a natural compound found in coffee beans.
Pectin typically decomposes during roasting and forms bitter-tasting compounds. However, when elephant gut bacteria reduce pectin levels before roasting, fewer bitter compounds are created, resulting in a smoother, less harsh flavour.
Scientists Call for Further Research
“Our findings may highlight a potential molecular mechanism by which the gut microbiota of BIC elephants contributes to the flavor of BIC,” said Associate Professor Takuji Yamada, describing the significance of the study.
He added that further experiments are needed to confirm the hypothesis. “A biochemical analysis of coffee bean components before and after passage through the elephant’s digestive tract would help validate these findings,” Yamada said.
Diverse Gut Microbes Play a Key Role
The study also found that elephants fed coffee cherries had a more diverse gut microbiome, including bacteria strongly associated with pectin digestion. Scientists believe that consuming coffee cherries may encourage the growth of these microbes inside the elephant gut.
Implications Beyond Coffee
Researchers say the findings demonstrate how animal digestion and gut microbiota can significantly influence food flavour. The study opens up new possibilities for using microbial processes to develop novel coffee-processing techniques and could also influence research into other fermented foods.
The findings were published in the peer-reviewed journal Scientific Reports.