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"One notable exception to this rule is with draught stouts. As odd as this seems, draught stouts’ carbohydrate amounts don’t measure up to their mouthfeel. Take Guinness Stout, for example. Guinness draught stout has an original gravity of about 9.5° Plato, contains about 4% alcohol by volume, contains about 120 calories per 12-ounce serving and has roughly 5.2 grams of carbohydrate (data taken from “Stout” by Michael J. Lewis; Brewers Publications, 1995). "