Some say that it tastes of caramel or chocolate. Others describe it as earthy and musty. Whatever the flavour, connoisseurs are happy to pay $41 to savour a single cup of luwak coffee.

That is quite a price for a brew made from beans digested and excreted by Indonesian civet cats, or luwaks.

It is being marketed in Australia as “the world’s rarest and most exclusive coffee,” although those with more sense than money refer to it as “cat-poo coffee.”

Allan Sharpe, co-owner of the Heritage Tea Rooms in Hervey Bay, Queensland, said: “People who willingly pay the $50 are uplifted by the thrill of the experience.”

Every month about a dozen people sample the café’s luwak coffee, which Sharpe and his wife, Michelle, have not yet promoted or advertised since it was first on the menu last November, relying on word of mouth.

“It’s as good as my private life is bad,” one taster said. “This is the kind of coffee you renounce your religion and sell your child for.”

Customers are rewarded with a “certificate of experience” as a memento of their drinking of luwak coffee. Others tell the Sharpes that even if they were paid to do so, they could not bring themselves to drink coffee from beans secreted by an animal.

Gift boxes of luwak coffee, also imported from Indonesia, include the animal’s droppings wrapped in plastic, which the Sharpes say are treated with gamma rays by quarantine officials on arrival in Australia.

The beans, which are gathered from forest floors by hand and initially resemble slabs of peanut brittle, are cleaned and lightly roasted.

The boxes, including 9 oz of coffee and the droppings encased in plastic, retail at $131.

It is not known when the first cup of luwak coffee was brewed, nor how the first cup came to be brewed from their excrement.

The most common theory is that those who harvest coffee beans realized that those contained in luwak droppings in Indonesia, the Philippines, Vietnam and south India were easier to gather from the forest floor than from the plants.

Annual world production is believed to be only about 660 lb., with a market price of about $987 a kilo.

Guelph University in Canada is one of the few institutions to have studied the make-up of luwak coffee beans. Its scientists found them to have less protein, a lower bacterial count and some pitting on the surface compared with the popular Colombian variety.

This may explain, the researchers said, why luwak coffee was less bitter and had a more attractive aroma.