Most breweries, whether a microbrewery, a brewpub, or one of the major mass-production breweries, offer tours of their facilities. This is an excellent opportunity to learn what actually goes on in a brewery, to see the brewing equipment and the raw ingredients, and to ask questions of the masterbrewer. Those 21 and older will be able to sample the various styles of beer at the brewery.

Homebrewing is a popular trend that has been growing rapidly for the past decade. Those 21 and over can learn firsthand how to brew small batches of beer at home. The equipment and ingredients needed to begin brewing can be found at some larger liquor stores or through mail order.

There are numerous books and magazines available on the subject. Zymurgy (https://www.homebrewersassociation.org/magazine/search-zymurgy-issues/), the American Homebrewers Association's magazine, focuses on homebrewing issues. The Brewers Association also lists publications on its Web site at https://www.brewersassociation.org/edu/brewers-publications/#searchModal. Most brewers began their experience with brewing by brewing first at home. So you're not of legal drinking age yet? Don't worry, you can still learn some of the basic skills of a brewer by making nonalcoholic carbonated drinks, such as sodas. Articles on this topic are frequently found in beer magazines because so much of the same equipment is used to make each.

Some breweries have part-time jobs available to students. They usually entail sanitizing the brewing equipment after a batch has been made or transporting heavy bags of ingredients. This is an excellent opportunity to learn how the brewing machines work, to get to know the various types of ingredients, and to see the types of challenges and pressures brewers face firsthand.

Brewers are concerned with all aspects of beer production, from selecting the exact blend and kind of flavoring hops, to the number of minutes the wort (liquid formed by soaking mash in hot water and fermenting it) boils. Beer styles and flavors are as multifarious as wine, and the craftbrewer can produce any number of beers for any occasion. Like great chefs, craftbrewers take particular pride in their recipes and enjoy presenting their "masterpieces" to others.

There are certain guidelines for each style of beer, but within those guidelines the brewer may experiment to create a truly unique flavor of a particular style. For example, a brewer who is making a pilsner must use bottom-fermenting lager yeasts (as opposed to top-fermenting ale yeasts), a light, dry barley malt (as opposed to a darker, roasted barley malt), and a specific few types of hops (most notably saaz, spalt, tettnanger, and hallertauer). With these basic guidelines observed, the brewer can experiment with such things as blending malts and hops, adding other flavors (such as honey, fruit, herbs, and spices), and varying boiling and lagering times.

The first step in brewing a batch of beer is for the brewer to decide what style he or she wants to brew. There are more than 50 styles of beer, many cousins of each other. Others are completely original and in their own class. All beers fall in one of two categories: ales or lagers. Among the more common styles many American craftbrewers brew are ales (including pale ales, brown ales, and Scotch ales), pilsners, bocks, and double bocks, stouts, porters, and wheat beers (commonly know by their German name Weissbier or Weizenbier). With a particular beer style in mind, the brewer will seek the best ingredients to brew it.

The four basic ingredients of beer are malted barley, hops, yeast, and water. Some smaller breweries may use a malt extract. Some beers may call for wheat, rice, or corn in addition to barley. Malted barley not only contributes to the flavor and color of the beer, but more important, it provides food (fermentable sugars) for the yeast to produce alcohol. Brewers have a host of different types of yeast to choose from depending on the particular flavor they seek. There are two main varieties, top-fermenting ale yeasts and bottom-fermenting lager yeasts, and within each of these two varieties there are hundreds of strains, each imparting a different flavor to the beer. Hops come from an herbal flower added to provide a contrasting bitterness and flavor to the sweet malt (called boiling hops), and to add a very important bouquet to the beer (called finishing, or aroma hops). Because beer is about 90 percent water, all serious brewers take the purity of their water very seriously. Water that has been treated with chlorine or that is rich in other minerals can impart unwanted flavors into a beer.

Malted barley must go through a mashing stage in the brewing process. Brewers grind the malted barley in specialized machines so that its husk is removed and the kernel broken. Next they add a precise amount of water and raise the temperature to between 150 and 160 degrees Fahrenheit to dissolve the natural sugars, starches, and enzymes of the barley. Brewers may vary the temperature and time of the mashing process to achieve a desired color or flavor. To complete the mashing process, the brewer strains out the barley grains. The remaining sweetened liquid, called malt extract, is now ready to become the wort.

Initially, wort is concentrated, unhopped beer. The brewer transfers the wort from the mashing vessel to a brewing kettle where boiling hops are added. This is usually just a matter of turning valves. Depending on the style of beer, the brewer will have selected a particular style or blend of hops. Some brewers use the actual hop leaf and others use a pelletized version. The hopped wort is boiled for an hour and a half to two and a half hours according to brewer preferences. After the wort has cooled to 50–60 degrees Fahrenheit for lagers and 60–70 degrees Fahrenheit for ales, the hop leaves or pellet residue are removed in a process called sparging, and the wort is now ready for its most vital ingredient, yeast.

To ensure quality and consistency, many brewers culture their own yeast, but some smaller brewpubs or microbreweries use prepackaged yeast. Once the wort is cooled, the brewer transfers it to a starting tank where the yeast is added and the fermentation process begins. Depending on the style of beer and the desired results, the brewer will choose either an open or closed fermentation. Open fermentation is less common because it leaves the beer susceptible to airborne bacteria. However, some styles of beer require it.

Most beers go through two basic fermentations; some beers require more. The initial contact of the wort and yeast spurs a fervent fermentation that produces alcohol and a foamy head called kraeusen. The brewer decides how long he or she wants this fermentation to last, generally between five and 14 days. After the desired time for the primary fermentation, the brewer transfers the beer to a lagering kettle (also called a conditioning kettle) where the beer is allowed to age. The fermentation continues but at a slower pace. The brewer must strictly regulate the temperature during the lagering time: 60–70 degrees Fahrenheit for ales, and 35–50 degrees Fahrenheit for lagers. After the desired aging or maturation of the beer, anywhere from two weeks to several months, the beer is again transferred to a storage tank where it is ready to be bottled. This step is necessary to leave any yeast or hops sediment behind so it is not present in the bottle or keg.

Brewers add carbonation to their beers either by injecting carbon dioxide into the storage tank just before it is to be bottled or kegged (this is typical of mass-produced beers) or, more common among craftbrewers, by adding a priming sugar, usually dry malt extract or corn sugar diluted in boiled water. If the brewer uses priming sugars, the beer must sit again for one to four weeks before it is ready to be served.

Brewing is both a creative and highly methodical craft requiring precise attention to detail. Brewers must monitor pH (acidity and alkalinity) levels in water and test water purity. They frequently use calculations to predict yields, efficiencies of processes, yeast maturation cycles, alcohol volume, bittering units, and many other factors. They study yeast physiology, metabolism, the biochemistry of fermentation and maturation, and the effects alternative brewing methods as well as bacteria, protozoa, and mold have on beer flavor and color. They constantly study methods of quality control and brewing efficiency.

Some craftbrewers at microbreweries may also help in bottling their beer. Workers at a brewpub (an establishment that is a combination brewery and restaurant) may stand behind the bar to pour drafts as well as work as waitstaff. At small breweries, brewers frequently sterilize their tanks, kettles, hoses, and other brewing equipment. Brewers who have the right resources and live in the right environment may grow, harvest, and store their own hops. Many craftbrewers are responsible for marketing their beer or designing logos. Some manage the brewpub or microbrewery. But a brewer's primary duty is always to brew beer, to experiment and come up with new recipes, and to seek out the right ingredients for the particular style of beer that is being brewed.