American soft drink giant Coca Cola has purchased a 10% stake in US brand Green Mountain Coffee Roasters, which manufactures Keurig single serve coffee machines. The two companies signed an agreement that will see all drinks within the Coca Cola range (including Coca Cola, Diet Coke and Fanta) turned into single-serve pods for use in Green Mountain’s upcoming cold-beverage machine. Expected to be launched in 2015, the device will enable …