The four most basic components of beer—barley, hops, water and yeast—remain unchanged from historical brews to modern beers. The fruit of golden prairies and verdant hop fields consummate the marriage that defines beer. Maltsters modify barley to render it fermentable, and toast it further to add color and character. Packaged malt extract is inherently no different than wort derived from a grain mash. Hops, in any form or variety, are available to all brewers. Recipe formulation is an art, involving critical ratios and combinations of dozens of types of hops and malt, catalyzed by a carefully selected yeast, in the first step of making a brew. Some recipes employ wheat or other grains, spices and sugar to augment the brew, but there is no getting away from the basic four ingredients of beer.
Malted barley corns are powerful, petite packages. Contained within the protective husk is a compact kernel that contains all of the flavor and enzymes necessary to provide the sweet, seductive wort that will eventually become beer. Crushing the grain is akin to liberation, analogous to grinding coffee; intact beans contribute little. Milling barley, however, is far from a simple act of grinding. The husk must be kept intact to provide a filtration matrix during mashing, and the kernel itself must be not be ground too fine, or it gets gummy. A simple rolling pin affords low-tech brewers the same character in extract worts as the all-grain brewers. But any all-grain brewer beyond that needs to heed the rules of the perfect crush to ensure a steady, clear stream of wort into the boiling kettle.
Beginning homebrewers produce wort by simply reconstituting dried or liquid malt extract derived from concentrated wort. But, from high-tech homebrewing upward, the most enchanting step of all takes place in the mash tun. The milled blend of base and specialty malts are mixed with hot water (or brewing liquor), and the indigenous enzymes magically convert the starchy component into a variety of simpler sugars that are either fermentable (maltose) or unfermentable (dextrine). The sweet wort is drawn off (or lautered) into the kettle, leaving the grain behind. Once boiling, hops are added at different intervals to provide bitterness, flavor and aroma. The now-bitter wort is further modified as the roiling liquid coagulates unwanted protein and both sterilizes and adds extra flavor via caramelization.