The global economic uncertainty is having a detrimental impact on the coffee industry in Southeast Asia - particularly in Indonesia and Vietnam.

The worst affected growers are those planting Robusta coffee, who tend to be the poorest of the region's farmers.

"One of the fundamental problems with perennial crops is that they often go through boom and bust cycles because farmers who are responding to higher prices plant the crops," he said.

"But in a case of coffee, it takes two to three years for the crop to begin producing and then when the coffee prices decline, farmers are somewhat locked in to the fact that they have coffee plants in production."