KEY POINTS:
For Nusamba Wurintara, the most prized arabica coffee beans on his plantation are not those growing on bushes but the ones he finds among the undergrowth, wedged in the excrement of wild palm civets.
These beans produce kopi luwak, a chocolate-flavoured coffee that is one of the world's most prized and expensive brews.
Each morning as he does his rounds of the plantation, Wurintara keeps his eyes open for civet excrement, marking each dropping with a stick so it can be collected and turned into kopi luwak.
"Civets are natural coffee pulping machines," said Wurintara.
His workers have strict instructions not to clear the neighbouring jungle, home to the shy, nocturnal civets, while signs around the plantation warn villagers not to shoot the animals, which are regarded as pests because they sometimes kill the local chickens.
The furry palm civets, which are about the size of a large cat, visit the plantation at night in search of the sweet ripe coffee cherries. They excrete the beans as they leave.
The 500-hectare plantation, which is set in the lush hills about 100km southeast of Medan, the provincial capital of North Sumatra, produces about 300 tonnes of arabica coffee a year, which sells for US$3600 ($5256) a tonne.
But while its crop of kopi luwak in a good year could amount to just 300kg, the beans sell for as much as US$100 ($146) a kilogram.
Merchants sell unroasted arabica civet coffee for up to US$500 a kilogram - five times the price of highly-prized Jamaican Blue Mountain. In the United States, this unusual Indonesian bean fetches as much as US$1200 a kilogram.
Intrigued by kopi luwak's mythical status, chemist M. F. Marcone travelled to Sumatra in 2004 to collect the beans for analysis.
"As the beans enter the civet's digestive system, an enzyme which breaks proteins into smaller parts interacts with the beans," said Marcone, an assistant professor at the department of food science at Canada's University of Guelph.
"The smaller protein will then react with the beans' carbohydrate or sugar during roasting, giving kopi luwak its famous, chocolaty, earthy and musty flavour," Marcone explained.
Kopi Luwak stands out in the world's fourth-largest coffee producer, where connoisseurs can enjoy a wide range of flavours.
Wirawan Tjahjadi, owner of Kopi Bali House, a coffee shop in the upmarket Sanur beach on the island resort of Bali, sells the civet brew for 200,000 rupiah ($31) for a pot - enough to fill three espresso cups.
"People who are curious about the taste of civet coffee don't mind paying the high prices," he remarked.
But some coffee experts question whether civet coffee deserves its reputation as one of the world's greatest coffees.
"Kopi luwak has unpredictable and inconsistent taste after roasting, mainly because of civets' wide diet which includes small rodents, eggs and fruits," said Alun Evans, who owns a coffee roaster in West Java.
"It is in many ways a novelty item. It's like going to a circus. It's entertainment, not a serious coffee," he added.
- Reuters