The American brewing scene is in full bloom, largely thanks to special little flowers called hops. The female flowering cones of the perennial Humulus lupulus bine (like a vine, but winds around a support to ascend) supply beers with flavor, fragrance and bitterness, which temper malt sweetness. Plus, hops serve as all-natural preservatives and help a beer’s foam head linger.
All hops aren’t created equal. Some impart sturdy bitterness, others bestow scents evocative of oranges or a pine forest.
Consider hops like spices. As with cooks, brewers blend varieties to devise distinct flavor signatures. When the hops are used during the brewing process is also important. When added earlier during brewing, hops produce more bitterness. Used later, when they’re exposed to less heat, hops emphasize aroma and taste. To boost bouquet, some brewers add hops to beer that’s either finished fermenting or is conditioning, a technique dubbed “dry hopping.”
In a moderate climate with ample sunshine and water, hop bines can grow up to one foot per day, possibly climbing more than 40 feet. The Pacific Northwest is the hotbed of America’s hop crops, while other crucial growing regions include Germany, the Czech Republic, the United Kingdom, Australia and New Zealand. (Hops are harvested in late summer and early fall.) Breeders are always creating new hop varieties in pursuit of making a memorable beer.
Whether hops are fresh, dried or freshly dried can impact their contributions. Here are the three main categories.
As soon as hops are harvested, the clock starts to tick. It’s a race to rush the plump, newly harvested hops from the field to the brew kettle. Brewers utilize the fresh flowers (ideally within 24 hours) to fashion the fleeting embodiment of fall—wet-hopped beer.
The field-ripe flowers retain an abundance of their prized oils and resins, which deliver a green, delicate vibrancy. Wet hops are most commonly showcased in pale ales and IPAs, particularly from breweries located near hop fields in the Pacific Northwest. With the spread of hop farms nationwide, however, wet-hop beer has slowly become an everywhere specialty. Remember: As fall disappears, so does wet-hop beer. So when you see them, make sure to drink them ASAP.
Sourcing wet hops can be a logistical hurdle for breweries. The second-best thing is to brew with fresh hops. They’re the first to be harvested and kiln-dried, which safeguards them from spoilage. The dehydrated flowers are immediately shipped to brewers (hops for Sierra Nevada’s “Celebration Ale,” for instance, arrive within seven days of harvest) who then use them to create intensely fragrant, flavor-loaded beers. Since harvest and kilning occur in late summer and early fall, some of America’s freshest pale ales are released during fall and early winter.
Beer does not necessarily follow the seasonal lead of heirloom tomato salads. To preserve the flowers for year-round use, the majority of hops are kiln-dried, ground to powder and made into pellets. Some breweries like Sierra Nevada and Victory prefer using whole-cone hop flowers, which they feel provide more flavor, rather than pellets.
The pellets, which look like vividly green rabbit food, are vacuum-sealed and held in cold storage until they’re ready to be used. (Oregon’s Crosby Hop Farm keeps its hops stored at 26°F.) The upshot is that brewers can make your favorite double IPAs in May.
Essential Hop Varieties to Know
Cascade is the foundational hop of American craft brewing. The cultivar was created by Oregon State University’s USDA breeding program, and released to the public in 1971. At first, there were few takers for this piney, citrusy flower with grapefruit complexity. That changed in 1975 when Anchor used Cascade (named after the Pacific Northwest mountain range) in their Liberty Ale. Cascade’s most famous home may be in Sierra Nevada’s flagship Pale Ale. Unveiled in 1980, Pale Ale helped definitively establish the boldly hopped, well-bittered template that arguably defines beers on the West Coast and in the U.S.
“Super Cascade” is the nickname of this citrusy, fairly floral variety with a fine bitter streak. Centennial was released in 1990, named after Washington State’s 1989 centennial celebration. Over the past two decades, Centennial has become the signature hop in many of America’s most respected pale ales and IPAs. It can be found in cultish beers like Bell’s Two Hearted Ale (look for pine and grapefruit rind) and Russian River’s Pliny the Elder, considered by many to be the original double IPA.
Deschutes, Widmer Brothers and Sierra Nevada partnered in the mid-2000s to fund research and development for a promising experimental variety suggestive of papaya, guava, citrus, mango and even lychee. Soon after its 2008 release by Hop Breeding Company, the newly christened Citra hop became one of brewing’s breakout stars. It helped usher in the new trend of tropically scented and flavored beers. Citra is essential to Deschutes’ Fresh Squeezed IPA, which also features Mosaic (see below).
The Hop Breeding Company parlayed the smash success of Citra with 2012’s Mosaic, a mélange of papaya, blueberry, tangerine and peach. Mosaic is reminiscent of the fruit punch of your youth. It sports an indelible flavor profile with incredible broad appeal. Mosaic has become massively popular. Its characteristics help define IPAs like Founders’ Mosaic Promise, Hop and Grain’s A Pale Mosaic and Karl Strauss’s Mosaic Session IPA.
Nelson Sauvin and Galaxy
New Zealand and Australia have been cultivating unique hops that American brewers have come to embrace. Most notably, Aussie-grown Galaxy is beloved for its starry profile of melon, peach and passion fruit. Meanwhile, the Kiwis’ fruity, white wine-like Nelson Sauvin will find favor with fans of Sauvignon Blanc. Sauvin, of course, is a nod to the grape variety that’s grown in New Zealand.
The Czech Republic and Germany are famed for hop varieties that accentuate aroma over bitterness. Saaz, Hallertauer, Tettnanger and Spalt (named after the cities where they’re cultivated) are known as noble hops, lending an herbaceous, zesty and sometimes spicy edge to pilsners and lagers.
Joshua M. Bernstein’s latest book, Complete IPA, is due out this month from Sterling Publishing.