A research team led by Associate Professor Takuji Yamada and Researcher Nodoka Chiba of the School of Life Science and Technology at the Institute of Science Tokyo announced on November 28 that it has revealed the possibility that gut microbiome are involved in shaping the flavor of coffee produced through fermentation in the intestines of Asian elephants. This was discovered by examining the gut microbiome in the feces of Asian elephants after they ate coffee cherries. The findings are expected to lead to the elucidation of a new mechanism by which gut microorganisms shape food flavor. The results were published in the journal Scientific Reports on November 18.
The taste and aroma of coffee depend not only on the type of beans and roasting method but are also greatly influenced by the processing method. "Kopi luwak" is a coffee that produces a distinctive flavor through passage through an animal's digestive tract; it is made by passing coffee beans through the bodies of civet cats. "Black Ivory Coffee," extracted from the feces of Asian elephants that have eaten coffee cherries at specific farms in northern Thailand, is also said to have a smooth taste.
However, the mechanism by which such distinctive flavors are produced had not been clarified.
In recent years, the gut microbiome has been reported to play a role in modifying food components and fermentation processes. The research group had previously revealed that Gluconobacter was the dominant genus in the guts of civet cats that produce kopi luwak, and that it may be involved in the degradation of bean surface components.
In the current study, the research group aimed to explain the relationship between the gut microbiome of Asian elephants and coffee flavor.
The research was conducted with individual project support from the Science Tokyo Fund.
First, the team analyzed genes contained in feces after Asian elephants ate coffee beans and discovered that gut microbiome such as Acinetobacter were present. Since these bacteria are also detected on the surface of coffee beans, it was suggested that they may be influenced by the elephants' gut microbiota.
The elephant feces were provided by Mr. Blake Dinkin, who operates an Asian elephant conservation organization and the Black Ivory Coffee company.
Additionally, functional analysis of the gut microbiota revealed that some of the Asian elephants' gut microbiome possess enzymes capable of breaking down components such as pectin found in the beans. Pectin is abundant in plant cell walls.
These findings suggest the fermentation by gut microbiome may change the chemical composition of coffee beans, adding a distinctive flavor and reducing bitterness to produce a smooth taste.
Furthermore, it was found that Asian elephants possess unique degradation pathways that are not found in other animals.
Yamada commented: "In the future, we aim to gain a deeper understanding of the natural fermentation process and flavor formation mechanisms by microorganisms by analyzing in detail at the molecular level how the gut microbiome of Asian elephants breaks down coffee bean components and change the flavor. This is expected to scientifically clarify the mechanism of fermentation by animal gut microorganisms."
Journal Information
Publication: Scientific Reports
Title: Preliminary study of gut microbiome influence on Black Ivory Coffee fermentation in Asian elephants
DOI: 10.1038/s41598-025-24196-0
This article has been translated by JST with permission from The Science News Ltd. (https://sci-news.co.jp/). Unauthorized reproduction of the article and photographs is prohibited.