KASARAGOD: Elevated levels of caprylic acid and capric acid methyl esters — compounds known for their flavour-enhancing properties and dairy-like aroma — are what imparts kopi luwak, also known as civet coffee, its aromatic and flavour profile, a team of researchers from the Central University of Kerala (CUK) has found.
Zoology department students Ramit Mitra, Thomas Jose, P Abhiram Krishnan and M Hariraveendra, guided by their professor Palatty Allesh Sinu, published their findings in the peer-reviewed magazine Scientific Reports.
Their research assumes significance in the context that they studied civet coffee in Robusta variety, which is predominantly cultivated in India, while the popular kopi luwak, produced by European companies at their units based in Southeast Asian countries such as Indonesia, is derived from the Arabica variety.
Considered one of the most expensive varieties of coffee produced in the world, kopi luwak is priced at $30-75 a cup. The global kopi luwak market is expected to exceed $11 billion by 2032.
The coffee is primarily prepared from the faecal matter of the civet cat (Asian palm civet, Paradoxurus hermaphroditus) which feeds on ripened coffee berries. The berries undergo digestion, absorption, and a natural fermentation process during their passage through the gut of the animal. While the pulp gets digested, the beans are excreted through their faeces. The scat samples are collected and further processed to recover the coffee beans, which are then roasted to obtain civet coffee.
Civet coffee is credited with enhanced flavours, aroma, specific chemical properties, and nutritional value. The research team collected the coffee beans from civet scat in Kodagu, the largest coffee-producing district in India. They collected 65 fresh civet scat samples from five estates — Balmany, Devarakadu, Margolly, Pollibetta, and Yemmigoondi.
The team also manually harvested berries, from which the pulp was removed using the natural-fermentation process. Following this, the normally occurring beans were sun-dried for seven days. While researchers stuck to the conventional method of coffee processing, they avoided deep roasting both samples of beans, so as to not significantly alter the acidity and concentration levels of the chemical parameters present, that could have led to a change in the aroma and taste profile. The civet scat beans and manually harvested beans were also subjected to scientific analysis.
The research concluded a significant difference in total fat content, wherein the civet samples had a significantly higher fat value than the manually collected samples.
Fat contributes significantly to coffee’s aroma and taste profile, which presumably plays a significant role in determining the flavour characteristics supporting the findings. Regarding the other parameters, there is no statistically significant difference between the two categories, the study said.
Total protein and caffeine content were found to be slightly higher in the manually collected samples, the study said, adding that the lower level of proteins, due to proteolysis, leading to shorter peptides and amino acids would contribute to the decreased bitterness of civet coffee. “The symbiotic Gluconobacter bacteria living in the gut of the civet cat could be producing the enzymes which provide the higher fat value. We are going to study this further,” Prof Sinu told TNIE.
