Whiskey, vodka, gin or rum…or tequila or brandy…made from wheat, barley, corn, potatoes, rye, sugarcane or any number of fruits—whatever the booze, Americans, the dominant drinkers of hard liquor worldwide, will go for it. But America’s love of hootch pales in comparison to its love of another drink: coffee. A new process that ferments liquor from used coffee grounds, then, may be just what the country is after.
The scientists first collected 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.
Microbrewers often flavor their beers with coffee, and caffeine-liquor mixes, from the classic rum and coke to the infamous Four Loko, are nothing new. But the new booze is different. The scientists say that their new “Spent Coffee Ground spirit” smells and tastes like coffee and “was considered as having features of a pleasant beverage.”
Plus, the potentially dangerous mix of caffeine and alcohol that gives boozy energy drinks a bad rap should be absent here: most of the caffeine, says Giridharan, “disappears in the brewing process.”
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