Caribou Coffee Co. is poised to become the first U.S. coffee chain to commit to buying coffee grown only under sustainable farming practices developed by the Rainforest Alliance.

Brooklyn Center-based Caribou currently buys about 80 percent of its coffee from farms certified by the New York-based Rainforest Alliance, a nonprofit group that works with farms that adhere to sustainable agriculture.

Tensie Whelan, the Rainforest Alliance's president, said Caribou plans to have all of its coffee sourced from Rainforest-certified farmers by the end of 2011.

"This is a total commitment," she said.

Chad Terwick, Caribou's senior director of coffee and tea, said the company has been gravitating toward sustainable-farmed coffee in recent years because of customer demand.

The company has chosen to work with the Rainforest Alliance because it's an independent third party, he said. "You want to be kept honest."

The Rainforest Alliance uses 150 criteria in certifying agricultural and forest operations for sustainable practices.

Those criteria include: soil conservation, minimizing waste and water use, protecting wildlife, curtailing chemical use and improving economic and social conditions for farm workers.

Mike Hughlett • 612-673-7003