What Are Hops? Everything You Need to Know

Read this to understand what hops are, why they are used and what they do. Along with benefits and growing techniques.

BREWING INGREDIENTS

Mat Stuckey

10/15/202312 min read

Hands holding fresh hops
Hands holding fresh hops

The Role of Hops in Beer: From Lager to IPA

Hops are the cone-shaped flowers of the hop plant, a key ingredient in beer brewing. They not only impart the signature bitterness and aroma to beers but also act as a natural preservative.

The Latin name for hops is Humulus lupulus. These unassuming green flowers have played a pivotal role in brewing for centuries, yet their tale stretches back far beyond the frothy glass.

Close up of hops
Close up of hops

1. The Role of Hops in Brewing Beer

Understanding the Hop's Contribution

When it comes to hops and beer, the connection runs deep. Here are some essential points about the role of hops in brewing:

  • Primary Ingredients: Hops are one of the four essential ingredients in beer brewing, alongside water, malted barley, and yeast.

  • Balancing Act: Hops lend a distinctive bitter flavour that counters the sweetness of malt sugars, striking a harmony in the beer's taste.

  • A Spectrum of Flavours: Beyond bitterness, hops deliver a variety of aromas and flavours, such as:

    • Citrusy

    • Piney

    • Herbal

    • Earthy

    • Floral

  • Historical Significance: The term "beer" in some languages is believed to mean "brewed with hops." Ancient beers may not have contained hops, but by the 11th century in Europe, hops revolutionised the brewing process.

  • Natural Preservative: Hops acted as a preservative, especially beneficial during times without refrigeration, significantly prolonging beer's shelf life.

  • Modern Beer Landscape: Today, while the world of beer is diverse, the centrality of hops remains. Whether it's a hop-forward IPA or a balanced lager, hops provide the nuance and distinction.

    Brewers around the world meticulously choose hop varieties and blends to craft their desired flavour and aroma profiles. So, whether you're a hophead chasing bold beers or someone sipping a light lager, the role of hops in crafting the beer's character remains undeniable.

hops next to a beer
hops next to a beer

2. Anatomy of a Hop

Appearance

Though delicate in appearance, hops provide immense flavour and aroma. The mature hop flower, or cone, is an oval-shaped structure made up of layers of papery bracts and leafy petals. Their colour ranges from pale green to golden, with a soft, textured feel. Inside are round, yellow lupulin glands full of resins and essential oils critical for brewing. The size of cones varies by variety, but generally they are 1 to 2 inches long.

Hops grow on climbing bines that can reach dizzying heights. Unlike vines, bines circle clockwise as they grow, using stiff hairs to latch onto trellises. The bines bloom and develop cones during lengthening summer days, reaching peak harvest time in late August to September in the Northern Hemisphere.

Family Ties

While hops have a storied past in brewing, their connection to another infamous plant is often noted. Taxonomically speaking, hops belong to the Cannabaceae plant family. That makes them close cousins to cannabis.

Botanically, they share similarities - hops are also flowering, climbing plants with resin glands. But they lack the psychoactive compounds THC and CBD found in cannabis. So while hops offer plenty of flavour, don’t expect them to alter your state of mind!

Instead, they contain antibacterial tannins and polyphenols. The main components prized in brewing are alpha acids, contributing the bitter taste, and hop oils that imbue those enticing aromas. In fact, brewers will often discuss hops in terms of their alpha acid percentage and oil composition.

hops growing in a field
hops growing in a field

3. Cultivating Hops: From Seedling to Harvest

Growing Conditions

Hops thrive in temperate climates with long daylight hours. They need a minimum of 14 hours of sunlight a day during growing season. Cool night temperatures below 60°F complement the warmer days hops favour.

Like grapes, the climate and soil hops grow in impacts their character. Certain regions like those in the Pacific Northwest produce hops with distinctive traits. Yakima Valley in Washington State provides ideal growing conditions, generating over 75% of U.S. hops.

As climbing plants, hops need vertical structures to grow properly. Growers construct tall trellises, allowing the bines to scale upwards of 20 feet high or more. The trellising also aids in harvesting. Well-draining, nutrient-rich soil is optimal, as hops will struggle in heavy clay or overly sandy soils.

While they can grow wild, hops cultivated for brewing require pruning and training for optimal yield. Proper watering, fertilisation, and pest management also foster healthy plants.

Planting to Picking

Hops are traditionally grown from rhizomes, or root cuttings, rather than seeds. The plants sprout as early as March or April, depending on climate and variety. Growers position the rhizome so that the buds point upward and provide a trellis for the shoots to climb.

The first year primarily involves training shoots up strings or cables. Minimal cones will develop as the plant focuses its energy on establishing an intricate root system. It’s not until years two or three that substantial hop flowers form for harvest.

Hop plants reach peak production between five and twenty years old. To determine ripeness, growers consider factors like the firmness of cones, resin content, and distinctive aroma of mature hops. The ideal harvesting window is narrow - too early and the hops lack flavour, too late and they deteriorate.

Commercial hop farms employ specialised harvesting machines that remove bines and strip cones efficiently. Home growers must hand pick each hop flower at optimal ripeness - a labour of love!

The Harvesting Process

The annual hop harvest is a mad dash, with growers racing to pick bines at their peak before they spoil on the vine. In major growing regions, trained pickers descend on farms to hand pick hops or operate harvesting machines over long days. The scene resembles the grape harvests of wine country.

Timing is critical, as hops mature rapidly but lose flavour soon after. Growers monitor alpha acids and oil content, which peak before cones reach full size. To catch them at their best, bines are cut down then transported immediately for picking and drying, before those coveted compounds deteriorate.

Post-harvest, hops must be dried and cooled quickly before conditioning and baling. Drying arrests development of compounds that cause off flavours. It also preserves the resins and oils that contain essential flavour and bittering attributes.

a grower touching their hops
a grower touching their hops

4. Post-Harvest: Preparing Hops for Brewing

Drying and Curing

After cutting, hops must be dried quickly - ideally within 24 hours. Growers have used various methods over the years, including wood-fired kilns. Today oven drying is common, blowing hot air through picked hops to reduce their moisture content. Temperatures, duration, and techniques vary based on hop varieties and growing regions.

This drying and curing process is delicate work. Drying too fast risks scorching hops. Too slow or cool develops mould and other problems. Proper drying results in hops that are springy with 8-12% remaining moisture content. The hops are then rapidly cooled to preserve aromatic compounds.

Conditioning follows, where hops spend 1-2 weeks “relaxing” in cold storage. This allows any remaining moisture to distribute evenly. After this flavonoid-forming process, hops are pressed into bales weighing 180 to 200 pounds and readied for use.

Storing and Using

Thanks to modern practices, dried hop cones can be stored for 1 to 2 years while retaining most of their brewing value. They are kept chilled, with controlled humidity, to prevent deterioration. Hop pellets and extracts allow even longer shelf life.

When using hops, brewers must factor in alpha acid and oil percentages, as potency fades over time even in well-kept hops. For small batch or home brewing, whole dried hops are ideal. Pellets are a less messy option, formed by milling dried cones into a compact powder.

Ideally hops are added to brews within a year, as older hops lose pungency. Hopheads looking to maximise flavour use recently dried “wet” hops in their recipes or dry hop during fermentation when aroma matters most.

multiple rows of hop plants at sunset
multiple rows of hop plants at sunset

5. Global Hop Havens: Where Are Hops Grown?

While hops thrive in temperate northern climes, they grow worldwide. Certain regions have reputations for producing hops with distinctive characteristics. These prime hop-growing areas include:

  • Yakima Valley, Washington: Accounting for 77% of U.S. production, the dry climate and volcanic soil creates hops with bold flavours. Yakima Valley is known for Citra, Cascade, and Simcoe varieties.

  • Willamette Valley, Oregon: Cooler temperatures and alluvial soils foster delicate hops like Willamette, a noble hop famed for its mild, earthy profile.

  • Kent, UK: Kentish hops from this historic English region contribute earthy, herbal notes to ales. Fuggle, Golding and E.K. Golding are well-regarded.

  • Hallertau, Germany: This Bavarian area produces the Four Noble hops revered in lagers, including Spalt and the spicy Saaz.

  • Žatec, Czech Republic: The Czech Republic supplies classic Saaz hops, lending a mild spiciness to many continental lagers.

  • Tasmania, Australia: Grown on the southern island of Tasmania, Galaxy and Enigma are fruity, pineapple-like hops used in juicy IPAs and pale ales worldwide.

  • New Zealand: Kamahi, Nelson Sauvin and Rakau contribute their quintessential tropical, Sauvignon Blanc-like traits to beers across the globe.

  • Himalayan Foothills, India: Indigenous to India, wild Himachali hops grow in the northern Himalayan foothills and lend uncommon depths to indigenous brews.

The Bountiful Benefits of Hops Used in Brewing

Hops play an indispensable role in the brewing process, infusing beers with their characteristic bitterness and nuanced flavours. Originating from the female flowers or hop cones of the climbing plant known as bines, they have long been cherished for the depth and dimension they bring to different beer styles.

The Role of Hops in Taste and Aroma

Hops are responsible for the bitter taste in beer, counteracting the sweetness of malts. However, their influence goes beyond mere bitterness. Different hop varieties, like the aromatic Nelson Sauvin or the popular Cascade hops, impart unique flavours and aromas. The rich tapestry of aroma hops can introduce notes ranging from floral to citrusy, from piney to fruity, thereby crafting the distinctive profiles of beers like those championed during the craft beer revolution.

Versatility through Varieties

With a plethora of hop varieties grown commercially, brewers have a vast palette to work from. Noble hops, for instance, are renowned in traditional European lagers for their subtle and balanced profiles. On the other hand, Centennial hops or British hops might be chosen for bolder ales or IPAs. Understanding the nuances between bittering hops and aroma hops can significantly influence the finished beer's profile.

Preservation and Stability

Beyond flavour and aroma, hops offer a protective edge. They act as a natural preservative, extending the shelf life of beers. This benefit traces back to times when hops were first incorporated into brewing, ensuring that the beer remained fresh during long voyages or storage periods.

Health and Wellness

Extracted from hops by boiling during the brewing process, certain compounds might offer health benefits, though beer should always be consumed in moderation. Research has looked into hops' potential antioxidant properties and other wellness attributes, though it's the delightful taste and aroma that most beer enthusiasts celebrate.

Driving the Craft Beer Movement

The annual hop harvest, especially in regions like Yakima Valley, fuels innovation in the brewing community. The rise of craft brewing has seen an explosion in the use of hops, with breweries continuously seeking out new and different hop varieties to create unique and flavorful brews.

In essence, the benefits of hops extend beyond mere taste. They encapsulate tradition, innovation, and the very essence of what makes a beer both refreshing and complex. Whether you're sipping a Sierra Nevada that highlights the brilliance of Cascade hops or exploring beers that push the boundaries of hop use, it's evident that hops are truly at the heart of brewing.

A hand holding hops
A hand holding hops

6. Use of Hops for the Homebrewer: Tips and Tricks

Beer Recipes and Hop Ratios

When designing beer recipes, brewers carefully consider how much and when to add hops. Hop amounts vary based on style - rich stouts need little, while IPAs brim with hoppy goodness. Here are typical uses:

  • Bittering hops: Added early in the boil, they contribute base bitterness without aroma. High alpha acid hops work best. An IPA may use .5-2 ounces per 5 gallons.

  • Flavour hops: Added mid-boil, flavour hops layer taste but still offer bitterness. A porter might include .25-.5 ounces per 5 gallons.

  • Aroma/finishing hops: Added late or post-fermentation, they provide fresh hop aroma. An APA could finish with .5-1 ounce per 5 gallons.

  • Dry hopping: Added to fermented beer, dry hops boost aroma. IPAs often get 1-2 ounces per 5 gallons.

These ranges demonstrate how heavily hopped styles utilise far more hops than malty beers. Brewers balance hop varieties, volumes and schedules to create their desired profiles.

Buying Hops

With a dizzying selection of hops available today, homebrewers must choose wisely. Seek out reputable suppliers selling vacuum-packed or nitrogen-flushed hops for freshness. Whole hops store better than pellets.

Consider hop varieties that will complement your beer style and provide the bitterness, flavour and aroma you envision. Buy in smaller quantities, as hops fade over months. For the fullest flavours, use fresh "wet" hops or dry hop during fermentation.

Exploring Flavours

One of the joys of homebrewing is experimenting with different hop varieties. Hops offer an astounding range, from citrus to tropical fruit to earthy herbs. Beyond bitterness, explore how hops impart other flavours like:

  • Floral: Hints of blossoms and perfume (Cascade, Amarillo)

  • Spicy: Black pepper, woodsy ginger notes (Chinook, Crystal)

  • Fruity: Grapefruit, melon, stone fruit and berries (Citra, Mosaic, Simcoe)

  • Piney: Coniferous forest and resiny flavours (Chinook, Columbus, Centennial)

  • Tropical: Mango, passionfruit, pineapple (Galaxy, Mosaic, Vic Secret)

  • Earthy: Grassy, herbal qualities (Fuggle, East Kent Golding)

Start by tasting hops raw - rub freshly dried hops to release their aromas. Then brew batches with single hop varieties to appreciate their contributions. With experience, you can blend hops for custom brews.

a hop farm
a hop farm

Conclusion: The Continuing Journey of the Noble Hop

While brewing practices have evolved immensely, hops continue their steadfast role, providing balance, preservation and enticing aromas. They turn the craft of combining water, malt, yeast and hops into an art form. With over 100 varieties grown worldwide, there are always new hop profiles to explore.

Understanding the science and anatomy of these plants allows brewers to coax out their most desirable characteristics. But at the same time, there remains an air of mystery about how growing conditions influence hops on a vintage-by-vintage basis. Their development and optimal use continues to challenge growers and brewers alike.

The intricacies of hops offer a lifetime of discovery for those seduced by their allure. Whether you're a hop aficionado or just beginning to appreciate these flowers, savour their journey from bine to brew. Let their story enhance your enjoyment of each sip.

Wherever your beer adventures lead, hops will be there contributing their unique imprint of bitterness, zest and aromatics.

Want more info, tips and tricks with beer ingredients or homebrewing? Head over to the Brewpedia blog for loads more!

FAQ About Hops

Q: What are hops?

A: Hops are the flowers of the hop plant (humulus lupulus) and are used primarily in brewing beer. They add bitterness, flavour, and aroma to the finished beer.

Q: How do you use hops in brewing?

A: Hops are typically added to the beer during the boiling stage of the brewing process. They can be added at different times to achieve different effects, such as adding bitterness when added early and adding more aroma when added later.

Q: What do hops taste like?

A: Hops have a unique taste that can vary depending on the variety used. They can have flavours ranging from floral and herbal to citrusy and piney.

Q: What are the different hop varieties?

A: There are many different varieties of hops, each with its own unique aroma and flavour characteristics. Some common hop varieties include Cascade, Centennial, and Saaz.

Q: How are hops grown?

A: Hops are grown on vines and require a trellis system for support. They are typically grown in regions with the right climate and soil conditions, such as the Pacific Northwest in the United States.

Q: Are hops used in beers other than craft beer?

A: Yes, hops are used in a wide variety of beers, not just craft beer. They are a key ingredient in traditional beer recipes and are used by many different brewing companies.

Q: Do hops have any other uses?

A: While hops are primarily used in brewing, they have also been used for medicinal purposes and have some similarities to the cannabis plant.

Q: How do hops give beer bitterness?

A: Hops contain alpha acids, which are responsible for the bitterness in beer. When hops are added to the boiling wort, the heat causes the alpha acids to be released and they then dissolve into the liquid, giving it bitterness.

Q: What is the role of hops in beer?

A: In addition to adding bitterness, hops also contribute to the aroma and flavour of the beer. They can give the beer a floral, citrus, or spicy character, depending on the variety used.

Q: Can you describe the taste of beer hops?

A: The taste of beer hops can vary depending on the variety used, but they are often described as having a bitter, herbal, or sometimes even fruity taste.

Written by Mat Stuckey