Chapter 3


(book excerpts)

Hops are the essence of beer brewing. They are the tiny cone-shaped flowers of the Humulus lupulus plant. Hops provide both bitterness, a variety of flavors, and aroma-enhancing powers to numerous beer styles. Furthermore, they are considered to have foam-improving qualities. Hops also have pronounced bacteriostatic activity that inhibits the growth of Gram-positive bacteria in the finished beer. Hops, when in high enough concentrations, aids in the precipitation of the more water-insoluble proteins in the kettle. Hops are classified according to their origin and type; for similar varieties, the influence of origin dominates. Classification by type is made on the basis of the content of compounds responsible for the bitter taste, flavor, and aroma. The main compounds that are found in hop cones are the soft resins (α- and β-acids), essential oils, and polyphenols. The alpha- and beta-acids are associated with flavor and bitterness of beer and essential oils contribute to the beer’s aroma. Hop polyphenols play a role in the establishment of the intrinsic colloidal stability of beer.

Click on the following topics for more information on hops.

Topics Within This Chapter: