Bitter and earthy. Fit for instant brews only. Robusta coffee has a dire reputation, but a small group of farmers in Vietnam are trying to turn its fortunes around as a warming world threatens the industry. "With the current situation of climate change and the global shortage of arabica coffee supply, people have to use robusta coffee as an alternative to arabica coffee, which doesn't satisfy customers' demand," says Pham Thi Diep Giang, deputy director general of Trung Nguyen, one of Vietnam's top coffee brands. IMAGES AND SOUNDBITES ARRANGED IN SEQUENCES