Photos: The making of an ethanol 'superbug'

Here's a close-up of the brown "beer" that Mascoma scientists are brewing. The experiments, which can go for days, will track how well a microorganism produces sugars and ethanol. In an industrial plant, the ethanol in the brew would be separated in a distillation tank and then shipped to be blended with gasoline.

Photo by Martin LaMonica/CNET Networks

Caption by Martin LaMonica