Use of Hops

• Hops are a relatively recent addition to the history of beer brewing. While beer has been brewed for thousands of years, it wasn't until the late 11th century that hops were used as an ingredient, and it took several centuries for them to gain widespread acceptance. Prior to the use of hops, plants such as mugwort and bog myrtle, as well as spice mixtures, were used to add complexity to the flavor of beer and tone down its malty sweetness.

  As hops began to gain popularity as a flavoring agent and supplant the older styles, it was discovered that the flower had a mild antiseptic and preservative quality as well. This discovery helped cement the place of hops in beer brewing, as hopped beer lasts longer than unhopped beer and is less likely to be infected by unwanted microorganisms.

Choosing the Best Hops

• As Charlie Papazian says in "The New Complete Joy of Home Brewing," "There is no one right hop for everyone." The selection of hops for brewing any beer is necessarily a subjective choice. There are dozens of varieties, each with its own alpha-acid content, flavor profile and aroma. Aspiring brewers will need to familiarize themselves with many hops to be able to match a specific hop to the beer they want to brew.

Types of Hops

• There are three basic categories of hops; bittering, aroma and dual use. Bittering hops are varieties containing high quantities of bitter alpha acids, and they are used primarily for that characteristic. Aroma hops generally have lower quantities of alpha acids and are used primarily for the distinctive extra flavor and aroma they give beer. Dual-use hops bridge the other two categories and can be used effectively as either, depending on when they are added to the mixture. It is not uncommon for a beer to make use of multiple hops from all three of the categories.

Noble Hops

• Noble hops are a commonly referenced subcategory of hops. They are European hop varieties that are extensively used in traditional beer styles, primarily as aroma hops. The most commonly recognized noble hops are hallertau, saaz, spalt and tettnang. Noble hops are not inherently better than other hop varieties, but they are essential to produce the characteristic flavors and aromas of many traditional European beers.

Hop Varieties and Beer Styles

• Although the kind of hops to be used in a beer is a subjective choice, there are certain styles of beer that have been traditionally associated with specific hop varieties. In these cases, it can be difficult to produce a beer of the desired style without using the traditional hops. Dark British ales, for example, generally call for goldings hops, whereas Pilsener lagers often seem off unless they include the spicy flavor of saaz. The American India pale ale--very different from the older British version--traditionally requires a citrus character best offered by cascade hops.

  There are far too many beer styles to list here, but a good strategy is to look at the hops called for in recipes in brewing books, regardless of whether you are going to follow those recipes. If a particular hop is really needed for the style you're brewing, it will usually show up consistently in those recipes.