Among today's big winners was Keurig Green Mountain ( GMCR.DL ), whose shares jumped 7.6% after Coca-Cola ( KO 1.39% ) said it will up its stake in the single-cup coffee brewer from 10% to 16%. Back in February, Coke said it would share its beverage portfolio with Keurig for the upcoming Keurig Cold countertop soda machine and take a 10% stake in the Vermont-based coffee roaster. Coke said, "These incremental purchases demonstrate our continued belief that Keurig Green Mountain has substantial growth potential," and, unlike its initial investment, these shares will be purchased on the open market, which will likely drive Keurig's share price even higher. Soda consumption has been declining domestically and Coke is looking for new ways to juice its growth. The Keurig Cold machine won't be out until 2015, so its popularity remains a question mark, but Coke's willingness to invest another $1 billion into its new beverage partner is certainly a sign of confidence in its future success.