"The Germans are particularly picky when it comes to their coffee," says Vietnamese coffee tester Le Anh Tuan, as he produces a testing sheet to note his findings, dpa reported.
The sheet mentions a number of palate sensations: moldy, woody, sour and tangy, among others. "The Germans reject any of these, thus ideally I must fill in a 'zero' for all," he explains, and then slurps noisily from a freshly brewed cup.
Germany's coffee drinkers are his most treasured customers, because the country is Vietnam's largest export market for coffee.
The South-East Asian country's coffee industry has experienced rapid development over the past 25 years.
Between 1980 and 2008 coffee plantations have mushroomed from a mere 22,000 hectares to currently half a million hectares, which makes Vietnam today the world's second-largest coffee producer behind Brazil.
In 2007, Brazil harvested 36 million sacks of 60 kilograms each, while Vietnam's harvest tallied in at 18 million sacks.
Number three producer Colombia trailed with 12 million sacks.
Some 85 per cent of Vietnam's coffee is cultivated in the central highlands, about 700 kilometres north of the southern metropolis Ho Chi Minh City, formerly known as Saigon.
Almost everyone in Buon Me Thuot, the capital of Dak Lak province, is involved in the industry one way or another.
An old woman lines up neat rows of almost-black coffee bean fruits to dry in the sun. Nearby, a man shovels the dried fruit into large sacks.
The owner of a funeral parlor displays caskets at the right side of his double garage, while he has converted the left into a café, in front of which he has heaped coffee bean fruits for drying.
Coffee farmer Nguyen Tan Huy and his wife Vo Thi Nhanh from Dak Lak's Krong Buk district are busy at work. With swift movements they strip the red and green coffee bean "cherries" from the branches.
In 2001, global output was 112 million sacks, but this year the figure is expected to reach 132 million sacks.
"We have produced coffee for some 100 years," says the chairman of Vietnam's Coffee and Cocoa Growers Association Luong Van Tu.
Annual production has reached about 1 million tons this year with an export value of roughly 2 billion dollars.
Vietnam primarily cultivates Robusta coffee. Higher-quality Arabica beans only grow at relatively cool, higher elevations, which Vietnam only has in the northern mountain ranges bordering China.
But the country already plans to increase its Arabica plantations there from the current 20,000 hectares to 100,000 hectares over the next few years.
Last year, Vietnam exported about 177 tons of coffee to Germany, 134 tons to the United States and some 95 tons to Spain, its three largest customers.
Despite increasing output, quality is still a major problem. It is estimated that up to 30 per cent of Vietnamese coffee exports are rejected as "sub-standard" in ports like Rotterdam.
"If the Vietnamese would produce less and instead put more emphasis on quality, that problem would not exist. Of course, there is competition, but the coffee market is large enough to accommodate every producer," Nestor Osorio, director of the World Coffee Organization, said at a conference in Ho Chi Minh City this year.
It appears that Vietnam has taken the hint seriously, because quality improvement has now become a government programme driven particularly by the Agro-Forest Research Institute in the western highlands.
Foreign organizations like the German Society for Technological Cooperation (GTZ) lend a helping hand.
Under the organization's tutelage, farmers learn how much water the trees need for optimal growth, how much fertilizer, and how the trees have to be pruned to enhance the harvest quality.
GTZ is also supporting several cooperatives striving to adhere to the so-called 4C (Common Code for the Coffee Community) standard that prescribes rules for sustainable coffee farming under social and ecological minimum requirements in production and processing.
As with other agricultural produce, more importers are putting importance on quality certifications.
A buyer for one of the large foreign importers is likely to pay a higher price for coffee under 4C certification.
Coffee drinking, meanwhile, lags far behind production and export. Only some 7 per cent of annual production stays in the country.
"I may drink a single cup in the morning to wake me up for the working day. But we are Asians. We prefer to drink tea," says farmer Nguyen Khee Tao.