According to Science Magazine, researchers have found a way to turn used coffee grounds into an alcoholic beverage. The scientists collected used coffee grounds from a coffee roasting company and dried them out. Then, they heated this “powder” in water at 163 degrees Celsius for 45 minutes. They separated out the liquid, added sugar and yeast, then let it ferment. After fermentation, they concentrated the liquid to increase the alcohol content (similar to how whiskey and rum are distilled).
The used grounds produced a beverage that was 40% alcohol. Reportedly it was described as smelling like coffee, while tasting bitter and pungent. The researchers think the flavor could be improved by aging and with further experimentation.
They say the caffeine is mostly removed during the brewing process, though… so it won’t keep you awake.