Last weekend, I was enjoying a leisurely café lunch when I spotted a $25 cup of coffee on the menu. That’s right, cup. My husband said he had asked about it on his last visit and was told it was made from coffee beans picked out of “some kind of ferret poop.” Suddenly it clicked. “Ooh, I just read a paper about this!” I said. Researchers recently reported a method to chemically fingerprint the coffee, called kopi luwak, which is widely faked as a high-priced luxury product.
Kopi luwak translates as civet coffee, and it’s made using coffee beans that have been excreted by a civet, often an Asian palm civet (Paradoxurus hermaphrodites). Civets look like a ferret crossed with a cat, and they eat whole coffee berries, digest the outer flesh (called pericarp) and pass the beans in their feces. These beans can then be washed, fermented and roasted, resulting in a coffee that some say is delicious. It’s certainly expensive, up to $200-plus per pound.
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My husband and I talked about ordering a cup. After all, as Gory Details blogger, I should really jump right in on the gross stuff, right? Then I started to search on my smartphone for the chemistry paper and came across a blog post that put the order on hold. Coffee trader Tony Wild made a plea on the Guardian website to end trade in civet coffee — begging to kill an industry that he created.
Wild brought the first batch of kopi luwak to the West in 1991. He thought its quirky, somewhat gross origins would make it a small-time novelty. Its ensuing popularity surpassed his wildest dreams. It became the “ultimate bling coffee,” he writes, served by appointment to celebrities in Santa Monica and sipped by Jack Nicholson in the film The Bucket List.
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As demand grew, so did the problems. Today, Wild estimates, production has grown from perhaps a few hundred kilograms to 50 tons or more per year and has spread from Indonesia to China, India, Vietnam and the Philippines. Civets are caught in the wild, put into small cages and forced into a coffee-berry diet. Or civet coffee is adulterated with regular coffee, or it’s faked entirely. Or other animals, from Brazilian jacu birds to elephants, are put into service as coffee-poopers. Asian palm civets were not listed as a threatened species by the IUCN in the most recent assessment in 2008, but animal welfare groups are concerned that as the coffee trade grows, trapping large numbers of civets could affect population numbers as well as harm many individual animals.
Wild now regrets his role in the whole affair. “I feel as if long ago I must have inadvertently put my finger on the pulse of some monstrous zeitgeist,” he writes, “a grotesque cancer that constantly mutates into yet more vile and virulent forms.” He has the depressing photos of civets with weeping open wounds crammed into tiny cages to back up his charges.
That’s where the scientists come in. Eiichiro Fukusaki of Osaka University in Japan and colleagues reported a method for authenticating civet coffee in July in the Journal of Agricultural and Food Chemistry. Using a common method called gas chromatography–mass spectrometry, the team analyzed the composition of kopi luwak and regular coffees from 21 areas in Indonesia. They took a metabolomics approach, meaning that they looked for a chemical fingerprint that would be produced only by a particular set of cellular processes: in this case, the digestion and excretion of coffee beans.
Along with higher ratios of inositol to pyroglutamic acid, higher levels of citric and malic acids turned out to be good indicators of real kopi luwak coffee, perhaps, the researchers suggest, because of passage through the civet’s gut with its gastric juices and microbial activity. Eventually, testing of commercial coffees could compare the beans’ overall chemical signature with that of known authentic and fake coffees and distinguish whether the product is real, fake or a blend of both.This research was aimed at verifying real versus fake kopi luwak, but as Wild has pointed out, there is another problem. Some civets are being farmed in appalling conditions, but of course all the coffee producers claim to harvest from either wild, free-ranging or humanely farmed animals. I e-mailed Fukusaki and asked him if he thinks there is any chance of distinguishing chemically between kopi luwak from farmed versus wild animals. After all, I suggested, a metabolomics approach might detect signs that the animal excreting the coffee has been fed an all-coffee diet, yielding different metabolic products compared with the more varied natural diet of civets, which includes rats, fruits, insects and even mollusks.
Fukusaki replied that he thinks the answer is “probably yes,” that metabolomics may be able to discern wild from farmed kopi luwak. His group even has some preliminary results, he says, but more testing and verification needs to be done.
While Fukusaki and colleagues look for ways to hold producers accountable, other efforts aim to stem the trade from the demand side. In September, Wild launched a campaign to end the sale of civet coffee. As a result, the British luxury department store Harrods removed kopi luwak coffee from their shelves and agreed to urge the Indonesian government to develop a certification for wild kopi luwak. The coffee had sold for £25 for 50 grams.
As for me, I never ordered that cup of civet coffee, and now I probably never will. I think that what Fukusaki’s team is doing is helpful, because now that the civet’s out of the bag there will probably always be a market for the product. So monitoring kopi luwak producers is a good thing. But for me, the icky thrill of drinking a cup of civet-poop coffee just doesn’t seem worth contributing to this trade.