Your Coffee Pods' Dirty Secret

Coffee brewing is in the midst of a revolution, and I'm not talking about the AeroPress. It comes in the form of a small 2-by-2-inch single-serving pod that requires a special machine. 

Keurig, owned by Vermont-based Green Mountain Coffee, makes the most popular pods, called "K-Cups." At the press of a button, the Keurig brewer punctures a small hole into the aluminum lid of an individual plastic cup filled with grounds, flushes it with steaming water, and, voilĂ ! Out comes one hot cup of joe. 

When Keurig launched its specialized brewing system in 1998, it might have come off as a bit niche. Not anymore. According to a survey by the National Coffee Association, nearly 1 in 5 adults drank single-cup-brewed coffee yesterday, making it the second most popular way to brew after the traditional drip methods—and far more popular than espresso machines.

The single-serve method has experienced impressive growth: According to the Seattle Times, while US consumers bought $132 million worth of coffee pods in 2008, they forked over $3.1 billion for them last year, compared to $6 billion for roasted coffee and $2.5 billion in instant coffee. Keurig also has similar brewing systems and pods for tea and iced beverages, and will roll out a system for Campbell's soup later this year.

Read full text in Mother Jones