Original gravity

Original gravity describes how many substances dissolved from the malt, mainly sugars, are present in the wort before fermentation. It is stated in percent by weight or in degrees Plato, so a value of 12 means about 12 grams of extract per 100 grams of wort.

During fermentation the yeast converts part of this extract into alcohol and carbon dioxide. In Germany, tax law classifies beers by original gravity into light (Einfachbier), Schankbier, full-strength (Vollbier) and strong (Starkbier) beers. Vollbier has at least 11 and less than 16 percent, Starkbier at least 16 percent. A higher original gravity generally means more body and more alcohol.