How Beer is Made
Beer is essentially the product of four ingredients: barley, hops, water, and yeast. Barley came to prominence as the grain of choice for beer because of its sweet, malty characteristics and because it was not as coveted in earlier days as wheat, which was necessary for making bread. Hops, a bitter and aromatic flowering vine that grows in temperate climates, is used to balance the sweetness of the malted barley. Water provides the medium for barley and hops to blend and for the beer to be consumed, and yeast converts the sugars of the barley-hops-water mixture (called wort) to the products of carbon dioxide (which gives beer a “fizzy” quality) and alcohol.
Barley must first be malted to be used for beer. This means that after barley grains are harvested from the fields, they are taken to a maltery, where they are wetted with water and heated (to replicate spring growing conditions) until they begin to sprout. At this point, the barley grains contain their maximum amount of starch (normally utilized by the maturing plant), so the malting process is halted with the addition of more heat. The conditions under which the barley grains are heated determine whether the grains will be light or dark and the amount of sweetness they will contribute to the beer. Brewers will use specific quantities and varieties of barley grains (called the grain bill) to create a desired style and flavor for the beer they are trying to create.
The grain bill, or malt, is added to the mash kettle vessel and saturated with hot water (called hot liquor) to make a malt “tea” or mash. The mash is kept at a certain temperature for an allotted amount of time to help the starch from the malted barley grain convert to sugars that eventually the yeast can feed upon. Once this conversion has occurred, the mash liquid is filtered from the spent barley grains through a lauter tun and transferred to the brew kettle, where hops are added at certain intervals and the mixture is boiled. The boiled mixture, or wort, is then rapidly cooled as it passes through a chiller on its way to the fermenter. Once in the fermenter, yeast is added to the cooled wort and allowed to begin the process of consuming the sugars and creating carbon dioxide and alcohol over the next two to three weeks. After fermentation, the new beer is drawn off of the yeast sediment and transferred (racked) from the fermenter into tanks where it is carbonated and conditioned for about a week. From there, the carbonated beer is moved (kegged) to either serving tanks (which are like giant kegs) or to kegs, which are stored for a month or more before they are tapped for consumers.