Though Trappist beers are brewed under carefully controlled conditions today—there are now computers in the breweries as well as copper vats—the basic process has remained unchanged for centuries. Malted barley is dried, ground to a flour, and soaked in water, to produce what brewers call the mash. As it soaks, the mash is stirred constantly by powerful motor-driven beaters. Next, it is passed through a filter where the draft, or spent malt, is separated from the wort—the liquid that is, at this point, to beermaking what grape juice is to the making of wine—which flows into the copper vats to be boiled. Hops are added both at the beginning and the end of the boiling stage, both to flavor the beer and to help precipitate out its nitrogenous matter, which would cloud the finished product.