Hops are one of the four primary ingredients of beer, the others being malted barley, yeast, and water.
Hops are cone-shaped flowers that grow on the hop plant, which is a fast-growing vine. The flowers are picked and dried or compressed into pellets before being added to beer.
There are three reasons hops are added to beer:
- The antiseptic qualities of hops inhibit the growth of unwanted organisms. In the 13th century brewers started using hops regularly because hopped beer didn’t spoil as quickly.
- Hops add bitterness to beer. Different varieties of hops have differing levels of bitterness, which is determined by the alpha acid content of the hops.
- Hops add aroma. Hops have a distinctive fragrance that is loved by beer drinkers.
There are many varieties of hops, each with its own unique qualities. Some have more alpha acids, making them better for adding bitterness, while others are less bitter and more fragrant, making them more suited for adding aroma.
Brewers often refer to hops as bittering hops or aroma hops depending on the qualities the hops add to the beer. The variety and combination of hops used by the brewer is part of what gives each beer its distinctive flavor profile.
While the hop plant can grow in just about any temperate location, Germany, England, and the northwestern United States are the primary hop-producing regions today. The climate and soil in each region makes it better suited for growing some varieties than others.
You can grow hops yourself, and many homebrewers do; all you need is a rhizome, which is cutting of the vine, and a little space.
The term “noble” hops refers to four ancient hop varieties: Hallertau, Tettnanger, Spalt, and Saaz. These ancient varieties are grown primarily in Germany and are generally used as aroma hops. New varieties are continually being developed by growers but the most popular varieties are Fuggles, Golding, Cascade, Centennial, and Willamette.