Hops are one of the easiest things for us to begin experimenting with as homebrewers. Regardless of whether your wort comes from extract or all-grain mashing, anyone can access and use a huge variety of hops for their homebrewed beer. Unlike slightly more advanced techniques like adjusting yeast pitch rates, carefully managing fermentation temperatures, and tinkering with water chemistry, changing up hopping can be an easy gateway to recipe design. Hops are ready to use in your homebrewed beer right off the shelf.
That being said, when to add hops to your beer makes a huge difference. Over the past few decades of amateur and professional brewing there have been different trends and techniques aimed to impart different hop character and intensity to beer.
IBU AND BITTERNESS
The most obvious hop character is bitterness, generally measured by International Bittering Units (IBU). IPAs typically sit somewhere between 40-60 IBUs, making them slightly more bitter than sweet. Imperial IPAs can clock in between 50-100 IBUs to balance a typically sweeter beer. It’s hard for humans to perceive much more bitterness than 100 IBUs, so anything boldly proclaiming to have an IBU above that is usually saying so as something of a marketing gimmick.
In the 1990s and into the early 2000s it seemed the beer world was staging an IBU arms race where breweries attempted to make the bitterest IPA. Something like trying to make the hottest chili pepper on the Scoville scale, brewing and drinking the bitterest beer possible became a badge of honour. While that’s all well and good, it also precipitated a myth that hoppy beers are inherently bitter which still turns some folks away from hoppy beers. In short, IBU is great for getting an idea of bitterness, but it doesn’t really reflect the hoppiness of a beer.
VERY BASIC HOP CHEMISTRY
For an in-depth discussion of how hops work we recommend reading Stan Hieronymus’ For the Love of Hops (Brewers Publications, 2012). The basics, however, go as follows: Hops contain acids called alpha acids (or humulone) in different quantities depending on the hop. When boiled these alpha acids are thermally isomerized (transformed from one molecule to another with the same components) into iso-alpha acids (or isohumulone) which provide bitterness.
Hops also contain volatile oils, primarily myrcene, humulene, and caryophyllene. These oils are much more delicate and provide much of the aroma of beer. When boiled for too long, or a beer is left to age too long, these oils break down resulting in beer that is less aromatic and flavourful than it ought to be. If you’ve ever found a several-months-old IPA on a store shelf and found it to be less than ideal, it’s because the oils from the hops have volatilized due to light, heat, and time.
ACIDS AND OILS
When we brew using hops, we are trying to balance two main components: acids and oils. Hop acids need heat (near boiling) to create bitterness. Hop oils are fragile and need to be infused in the beer without too much heat contact. It’s a careful balance to get the most out of hops for both their best bittering and aroma contributions.
Most classic recipes which call for a typical 60-minute boil suggest adding hops as soon as you reach a boil, somewhere near halfway through the boil, and somewhere near the end of the boil. This approach allows for a decent blend of acid isomerization and oil retention, however, like all things in homebrewing, there are constantly changing trends and approaches.
FIRST WORT HOPPING
First wort hopping involves adding your bittering hops to your boil kettle before you add wort to the kettle. Some anecdotal evidence suggests that this may impart a more complex bitter character to beer than the standard 60-minute addition. Recent experiments, however, have questioned whether it is a difference that makes a difference (see Marshall “The Brulosopher” Schott’s experiment here: http://brulosophy. com/2015/07/06/the-first-wort-hop-effectexbeeriment-results). Regardless, first wort hopping makes it easy to not forget your bittering addition when you reach a boil and allows hop pellets to break down before reaching a boil, reducing a chance for a boil over, so at least in terms of the pragmatics of your brewday, it might be an option worth trying.
Like first wort hopping, mash hopping is a technique that has hops being steeped prior to the boil. Mash hopping involves adding some hops to the mash itself with the intention of gaining more complex bitterness while (potentially) also gaining some aroma effects as the hops are supposed to infuse their flavours deep within the mash.
One of the easiest methods for imparting hop aroma into your beer is to add all of your aroma hops after the kettle has been turned off and allowed to steep for a few minutes to half an hour. As these hops will not boil, more of the oils will be retained while only some of the acids will be isomerized, reducing the bitterness component.
This method has rapidly become one of the most popular methods to create very aromatic IPAs. It involves a little more work, but creates a powerful hoppy effect. The kettle wort is cooled a few degrees below boiling (75-85 C) and then the wort is recirculated from the bottom to the top of the kettle to create a whirlpool in the kettle. This ensures the hops are broken down and mixed into the beer while the lower temperature allows for less isomerization and more oil retention.
A more intense version of this method, hopbursting, relies on all the hops being added at either whirlpool or flameout. Proponents of this approach argue that with high hopping rates enough of the acids will be isomerized at a near boiling temperature. Hopbursting is a technique with a growing school of adherents, so it is an approach to explore.
The easiest way to guarantee oil retention is to add hops without any heat. Adding hops to finished, fermented beer to steep for three to seven days (or longer, though too long can impart grassy flavours) can allow for intense aromatics without any bitterness contribution. Dry hopping is a perfect example of how a beer can become hoppy without the associated bitterness. Generally, it is recommended to dry hop in a secondary vessel, as it is more effective when the beer is essentially brite (without any yeast left in suspension).
FINDING YOUR OWN WAY
These techniques are not the only ways to hop! Other methods like hop rockets and torpedoes can also be explored and fun to experiment with. The key to hopping is to make a beer that has the bitterness and aroma you desire. Bitterness is intended to balance the inherent residual sweetness in the beer, so instead of thinking about it as a range for a particular style, look at how sweet your final beer will be and balance it to your tastes. There are so many varieties of hops and ways to use them that there is no limit to how to impart that perfect hop character to your beer. Just remember: drink it fresh!
Brew Folly’s American Farmhouse Ale
At Folly we have introduced a rotating American Farmhouse Ale that uses a blend of two different hops. This is an example of where a beer can be hoppy without a great deal of bitterness (only around 30 IBU). Since this beer finishes quite dry there is little need to go crazy with the bittering hops. Instead we focus on flameout and dry hops to impart flavour to this hoppy but not too bitter ale.
OG = 1.062 (13.5 °P)
SRM = 5
ABV = 6.2% (FOR A 20L BATCH AT 70% EFFICIENCY)
IBU = 30
3.50 kg (7.7 lbs) Weyermann Pilsner Malt
White Labs American Farmhouse Blend (WLP670) (or Escarpment Labs Fruit Bomb Blend, which is what we use at Folly)
If using White Labs build a starter two days prior to pitching (Escarpment Labs pitches do not require starters if fresh).
On your brew day, bring 14 litres of water to 74°C (165°F) and begin your 60-minute mash rest. After initially adding your grains, your mash temperature should drop to 66°C (152°F). After the 60-minute mash is complete be sure to add your first wort hops to the kettle then, sparge with 16 litres of 76°C (169°F) water to collect 24 litres of wort.
This brew will require a 60-minute boil. Hops can either be added at flameout or you can try using one of the methods described above like whirlpool.
At the end of the boil, cool the wort to 18°C (65°F) and pitch the mixed culture and ferment for three weeks. If bottle conditioning this beer, ensure that your gravity has stabilized before priming (with between 90-100g of dextrose).