Top image by dongga BS via flickr.
Researchers led by University of Minho bioengineer Solange I. Mussatto relay their findings in the September issue of LWT - Food Science and Technology. Science's Nisha Giridhan gives a tidy summary of the team's process [emphasis added]:
The scientists first collected this raw material from a Portuguese coffee roasting company and dried it. Then they heated the powder in water at 163°C for 45 minutes, separated out the liquid, and added sugar. Next, the team mixed in yeast cells, let the concoction ferment, and concentrated the sample to get a higher alcohol content. (A similar process is used to produce other distilled beverages such as whiskey and rum from wheat and molasses.) And voilà! Used coffee grounds produced a new alcoholic beverage with 40% ethanol.
The researchers call their creation "a spirit from spent coffee ground," or "SCG spirit" for short. According to eight trained taste testers brought on to evaluate the SCG spirit, the researchers write their boozy brew "was considered as having features of a pleasant beverage, with smell and taste of coffee."
The one down side is that most of the beverage's caffeine content is stripped during the brewing process. Which, then again, is maybe a good thing?