Hops in Beer Brewing

Hops used in beer brewing are the flowers of a plant known as “common hops,” with the scientific name “Humulus lupulus.” Adding hops during the brewing process aims to impart a unique bitterness to the beer and a rich aroma at the end of the brewing process. Another major benefit of adding hops to beer is that they act as a natural preservative, extending the beer's shelf life. As the popularity of hop aromas continues to grow—as experienced in IPA beers—increasing numbers of breweries are beginning to use larger doses of aromatic hops and add them at more stages of the brewing process.

What are hops in beer?

Hops are flowering plants, also known as hop plants. They are climbing plants with conical inflorescences. The inflorescences contain yellow pods. These small yellow pods are called hop cones and contain resin and essential oils. Hop cones are responsible for the aroma, bitterness, and flavor of beer.

Hops thrive best in temperate climates with fertile soil and ample sunlight. These ideal growing regions are typically found on opposite sides of the globe at similar latitudes.

Why are hops used in beer?

Craft brewers seek out hops to enhance the taste, aroma, and bitterness of beer and balance the sweetness of malt. Hops can be added at multiple stages of the brewing process to adjust the taste, bitterness, and aroma.

The benefits of hops

Hops are so versatile in craft beer that brewers can almost create any flavor they can imagine. Hops also serve another purpose in beer: they provide built-in antimicrobial properties. The acids in hop resin have antimicrobial properties that help inhibit the growth of spoilage bacteria during fermentation. This protective effect extends to the finished beer, where hops can also help prevent off-flavors from developing.

When are hops added during the brewing process?

Hops can be added at three different stages of the wort, depending on their role in the beer (flavor, aroma, or bitterness). The same variety of hops can be used for all three purposes, or different varieties can be used. Typically, all beers have at least one type of hops added to the wort to add bitterness and balance the sweetness of the malt. Without bitterness hops, the beer would taste overly sweet and cloying.

Most beer recipes will specify the timing for adding hops. For example, if the beer requires a 60-minute boil, the recipe may specify adding bittering hops after 30 minutes of boiling.

Bittering hops are typically added when the wort is gathered in the kettle and begins to boil. Aroma hops are added during the final 15 to 30 minutes of boiling. This imparts a fresh hop flavor to the beer without adding bitterness. Flavor hops are typically added during the final five minutes of boiling. This is because these hops are volatile, and prolonged boiling would cause their aromas to evaporate.

How to brew beer with hops

Dry hopping (adding hops during fermentation) and other techniques can add aroma without adding extra bitterness. Wet hopping is also becoming increasingly popular, but due to logistical difficulties, it is still uncommon at present.

• At the start of the brewing process, barley malt is ground, boiled, and mixed with other grains and sugar sources as needed.

• The brewery adds malt to warm water to activate enzymes. These enzymes produce a thick, sugary liquid called wort. The wort is then filtered from the malt mash for the next step.

• Hops are added to the wort and boiled. Boiling the hops turns the sweet wort bitter, but more hops can be added after the wort cools to enhance the flavor.

• Yeast is added to the cooled beer, and fermentation begins. Fermentation time varies depending on the beer style.

• The final step is filtration and storage. Filtration removes particles, but over-filtration may make the beer too pure, which may not suit many people's tastes.