The brewing of beer is an ancient practice, and although the variations of ingredients and processes are beyond count, there are commonalities shared between all beers.
Water: The basis of life is also the basis of brewing. Its basic clarity and mineral content can make a huge difference in the outcome of the brewing process.
Malt: Malted barley is barley that has been partially grown, then dried out in a kiln. This makes the starches available for the enzymes to convert into fermentable sugars. Specialty malts are kilned at different temperatures for different times to produce a wide array of colors and flavors.
Yeast: A member of the fungus family, yeast is the catalyst that transforms the hopped cereal solution into a beer. The yeast gets its energy for growth from the sugar solution in the mash provided by the malt. Alcohol and carbon dioxide are the waste products of its reproduction cycle. The yeast cells clump together in fermentation, foaming to the surface in some beers like stout, or sinking to the bottom as they do in lagers. There are numerous kinds of yeast, each giving its own unique flavor and quality to a brew.
Hops: The flower of Humulus lupulus. This flower contains a resin that is responsible for bitterness and hop aroma in beer. Without the hop, beer would be too sweet, not as flavorful, and not nearly as refreshing.
Adjuncts: Numerous other ingredients may be added in the process of brewing to give a beer its distinctive flavor and aroma. Items such as maize, barley, malts, sugar or rice may be added to change the alcohol, flavor, or appearance. Recipes may also use spices, herbs, honey, chilis, or fruits to flavor beers or change the appearance.
Original Gravity: The Original Gravity is measured before fermentation begins. We measure the weight of the beer as compared to pure water. Pure water measures 1.000. This gives us an indication of the amount of dissolved solids (mostly sugars) in the beer.
Final Gravity: The Final Gravity is measured after fermentation is complete. We compare original gravity and the final gravity to calculate the percent alcohol. This number can sometimes give an indication of the body of the beer. The higher the F.G., the more full bodied a beer may seem.
Standard Reference Measure: This is what we use to compare color of beer. The higher the number, the darker the beer.
International Bitterness Units (IBUs): These are the units we use to compare bitterness. A higher number usually means a more bitter beer.
Alcohol by volume (ABV): Beer typically falls in the range of 4%-6%, though it is available in various forms from ultra light at 2% to extremely strong at 12%. For comparison, wine is usually in the region of 12.5%-14.5%, and whisky 40%-55%.