Hopping Techniques
In this article we cover all known hopping techniques, including mash hopping, first wort hopping, hopping for bitterness, flavor, and aroma, and dry hopping. To fully understand these principals, one must have a concrete understanding of the notion of hop utilization.
Hop utilization is based on the isomerization of alpha acids in a given amount of hops when applied to the boil time factor. In plain English, we’re saying that there is a measurable chemical reaction and release of bittering, flavoring, and aromatic components from hops based on the amount of time that the hops are heated in your brew kettle. Hop bitterness is measured in international bittering units, or IBUs. Hop flavor and aroma is measured in your mouth and nose. Here are some hop utilization numbers from an online recipe program via www.tastybrew.com – based on a basic recipe of American 2 row pale malt brewed to 1.063 original gravity and one ounce of Amarillo hops used throughout.
• Mash hopping (148 degrees F. – 155 degrees F.) = .081 utilization
• First wort hopping (155 degrees F. – 200 degrees F.) = .135 utilization
• 90 minute boil = .239 utilization
• 60 minute boil = .223 utilization
• 45 minute boil = .205 utilization
• 30 minute boil = .172 utilization
• 15 minute boil = .111 utilization
• 5 minute boil = .045 utilization
• Flame out / 0 minute addition = 0 utilization (variable, depending on cooling time)
These numbers tell the story of just how much hop bitterness, hop flavor, and hop aroma will be wrapped up in your beer. The general rule of thumb is that the longer you boil a hop the more bitterness you will extract from it. This rule, however, is not infinite. Hop utilization is based on a finite possibility of IBU extraction and usually peaks around 90 minutes of boiling. Boiling hops for longer than 90 minutes, say 120 minutes, will only result in minimal gains of bitterness.
The numbers above represent an example based on a particular starting gravity, with a particular amount of hops, using one particular formula. Different brewing software will yield slightly different results based upon the use of a few closely related utilization formulas. Here is another chart, based on a related utilization formula, that actually graphs out the hop utilization of a 1.050 starting gravity brew.

Now, let’s take a look at the various hopping techniques.

Mash Hopping
Mash hopping is perhaps the most controversial and least used method of hopping in all of homebrewing and commercial craftbrewing. This hop application is basically an addition of hops to the mash itself, for whatever amount of time the grains are mashed, recirculated, and run off. This early process hopping contributes a relatively small addition of bittering units, but interjects a healthy dose of hop flavor.
Pellet hops are typically preferred for this method due to their ability to break down and be absorbed into the mash, with the notion that the small hop particles will pass through the entire process and end up in the brew kettle. Whole leaf hops can also be used for this method. While whole leaf hops may not pass through the mash as effectively as pelletized hops, they still do a great job of flavoring (with some small amount of bitterness). Whole hops added during mash hopping also have the added bonus of increasing the filtration of the grain bed as it compacts during recirculation.
Commercially, this method of hopping is used by Vinnie Cilurzno at Russian River Brewing Company for the highly acclaimed Pliney the Elder, Imperial India Pale Ale. This method of hopping was also used for the 2007 and 2008 winners of the “Best Damn Hoppy Beer in the Pacific Northwest” at Hop Madness. This technique applies only to all-grain and partial-mash brewing. Also keep in mind that the flavoring compounds extracted during mash hopping are best drawn from hops that have favorable oil and resin levels.
First Wort Hopping
First wort hopping is a traditional German method of pre-boil hopping that adds a smooth layer of bitterness, as well as a substantial addition of hop flavor and aroma. One can liken the effects of first wort hopping to that of a 20 minute hop addition. Hop utilization is similar, as shown in the previously listed example, with first wort hopping yielding .135 utilization versus .141 utilization with a 20 minute addition.
This method of hopping can be done with either whole or pelletized hops, and takes place as you begin your initial run off of wort (post recirculation) from you mash. The warm first runnings of wort saturate the layer of hops laying at the bottom of the brew kettle. The magic takes place as the hops release certain flavor and aroma compounds during this typically extended time period, at specific temperatures (150 degrees F. – 175 degrees F.).
Traditionally, first wort hopping was used in German lagers and Czech style pilseners. Noble hop varieties like Saaz, and domestic hybrids of this hops like Mt. Hood, Liberty, and Crystal, all work well for these delicate brews. First wort hopping also works well in “supercharging” Amercian ales (pales, ambers, and browns), IPAs, and Imperial IPAs. Some of the higher gravity American ales just can’t get enough hop. High oil content American hop varieties such as Simcoe, Horizon, and Summit are very effective at imparting a smooth bitterness and loads of hop character into a beer. Old stand bys like Cascade and Centennial can also readily fill this roll.
Some brewers have employed first wort hopping to eliminate the standard bittering addition (90-45 minutes). They will use a larger dose of hops, pre-boil, to hit their targeted IBU level, and also benefit from the intense boost in hop flavor and aroma. Other brewers have used first wort hopping to eliminate the 30-15 minute hop additions in their brews. In this instance, the reasoning is that a 30 minute hop addition becomes unnecessary because the first wort hopping has already compensated by adding the required IBUs and flavor.
Bittering Hop Additions
Adding hops at the beginning of your boil, boiling anytime between 90-45 minutes, will give your beer most of bittering. This technique is fairly straight forward, and is common in all forms brewing. Most brewers prefer to use a high alpha acid style of bittering hops at this point. Bittering hops can be either clean (neutral), or harsh (coarse). Different beer styles will dictate which property you seek from your hops. For example, a clean German pilsener lager would call for something with a clean bittering addition, such as a small addition of Magnum hops. Comparably, a big American style West Coast IPA would work best with something more aggressive like Chinook or Columbus hops.
Lower alpha acid hops such as Cascade, Golding, and Crystal can also be used at this point in the brew, but one must be cautious. You will have to use a significantly greater quantity (generally two to three times the amount) of lower alpha acid hops to achieve the same level of bittering units. This can be extremely cost prohibitive in these days of hop shortages and inflated market prices. Also, when used in greater amounts these lower alpha acid hops can begin to input some slight off flavors to your brew. Flavors such as dandelion, vegetable, and fresh cut grass have been reported. This is not to say that it can’t, or shouldn’t, be done – it’s just not highly recommended. I’ve had beers that have been brewed with 100% Cascade, as well as 100% East Kent Goldings, and they were great beers. A general rule of thumb could be that these low alpha hops could be used to bitter successfully in lower gravity beers, while your higher gravity beers will require hops with higher levels of alpha acids to get the job done.
Some examples of clean, or neutral, bittering hops would include Magnum, Bravo, Nugget, and Horizon. Some examples of coarse, or harsh, bittering hops would include Chinook, Galena, New Zealand Pacific Gem, and Millenium.

Flavoring Hop Additions
This 30-15 minute hop addition imparts most of the hop flavor to your brew, and at the same time will also contribute a decent portion of IBUs. A variety of hops can be used at this point in the brewing process – higher alpha, high oil hops like Simcoe and Columbus, or lower alpha hops like Mt. Hood or Cascade – but the best fit here is what we call dual purpose hops. Dual purpose hops are capable of providing an ample amount of bitterness as well as a potent flavoring addition. These hops typically fall into the 7-11% alpha acid range. Hops in this category would include, but not be limited to, varieties such as the New Zealand Cascade, Centennial, Amarillo, Northern Brewer, and Perle. In larger quantities these hops can be used effectively for bittering at the 90-45 minute additions, and can just as easily serve as an aroma only hop at the 15-0 minute addition.
Aromatic Hop Additions
When added with 15 minutes or less remaining in the boil, hop additions will serve primarily as producers of aroma, and provide little, or no bittering contribution. Traditionally, lower alpha acid hops are used at this point in the brewing process. These hops are used because (for the most part) lower alpha acid hops have a stronger aroma profile than higher alpha acid hops. This, of course, is dependent upon the oil level within the hops, but can serve as a general rule. Also, keep in mind that during these aromatic hop additions, more hops = more aroma, so formulate your late hop additions accordingly. Your American pale ale will need more hop aroma than your Northern English brown ale, and thus require a heavier late hop presence.
Aroma hops include Cascade, Golding (both English and domestic), New Zealand Riwaka, Sterling, and Fuggle. Most European noble hops would also fall into this category, and include varieties such as Hallertau, Spalt, and Saaz. Domestic breeds of the Halertau – Liberty, Crystal, and Mt. Hood - also make for great late addition hop choices.
Contrary to most classic brewing practices, a number of modern American craft brewers have started using high alpha acid, high oil content domestic hops for late kettle aromatic additions. These brewers often use reckless amounts of new, “designer” breed hops like Simcoe and Summit with great results. These hops, and similar breeds, are all exceptionally pungent and their aromatic properties are quite noticeable when you stuff your nose into them. Simcoe is super piney with a hint of restrained citrus, Columbus is extremely fresh flowery, and Summit is almost tangerine like with a dash of onion.
Dry Hopping
Dry hopping is a post boil method of adding hop aroma to a beer. Hops, either whole or pelletized, are added directly to the secondary fermenter, and left to sit for a specified amount of time. Ideal dry hopping times usually last from five to ten days. Not enough time on the dry hops and you’ll miss the flavor contribution that you seek. Too much time on the dry hops and you may pick up some off flavors, not unlike those picked up from using large amounts of lower alpha acid hops for bittering – grassy and vegetable-like are not uncommon. Dry hop amounts should be comparable to flame out (0 minute) amounts – the more dry hops in a fermenter, the more hop aroma will be produced.
One should at all costs avoid using dry hopping during the primary fermentation. Primary fermentation is an extremely volatile process, and nearly all contributions from dry hopping would be negated by the activity of the yeast in the beer. Simply put, dry hopping becomes lost during primary fermentation. There is also the small chance (extremely slim) of infection occurring if hops are added prior to fermentation.
When hops are added to the secondary there is even less of a chance of contaminating your brew. What? But you’re talking about adding an un-sanitized foreign ingredient to your beer! Exactly, and there are two reasons why you shouldn’t worry about this. First, there is a wall of freshly generated alcohol that is present in your beer in the secondary fermenter that will fend off almost any infection. The second reason is that hops are both antiseptic and preservative by nature, and under normal brewing conditions, don’t lend themselves to breeding beer infections.
Certain beer styles really take to the dry hopping technique, particularly English and American ales. ESBs, pale ales, ambers, reds, browns, India pale ales, and barleywines can all be dry hopped. All of these beers can greatly benefit from the added aroma of this process. Dry hopping is rare in darker beers like porters and stouts, lager brewing, and most Belgian beer styles.
Try to avoid harsh bittering style hops when dry hopping. Chinook, Galena, and similar varieties can input some awkward characteristics when added away from early in the boil. They simply lack the flavor compounds that one seeks from this type of addition. Typically, if a particular hop smells good, it will serve as a decent candidate for dry hopping.
Glass carboys are often difficult to clean, so most people find that it’s easier to use pelletized hops with this style fermenter. Pellet hop sludge is easily removed from a glass jug with warm water. Plastic bucket style fermenters are far more versatile for dry hopping due to their open design and ease of cleaning. The more desirable whole leaf hops can be thrown in without worry of extraction.
Dry hops can also be added in leaf form, in a hop bag, during the kegging process. The hop bag sits on the surface of the beer, partially submerged, following the level of liquid towards the bottom of the keg. One can acquire an extremely hoppy beer by the time you get to the end of the keg.
A number of people have argued that dry hopping also lends to hop flavor in a beer. This argument has been dismissed though, as scientists have concluded that the hop compounds released during dry hopping can only generate aromatic properties. The sensation of flavor and aroma are so closely linked that one can easily perceive aroma as flavor, and vice versa.

Hop Recommendations
Hops for first wort hopping –
• Simcoe
• Columbus
• Summit
• Goldings (English or domestic)
• Centennial
• Saaz
• Liberty
• Mt. Hood
• Crystal
• Cascade
Hops for bittering (clean)
• Magnum
• Bravo
• Nugget
• New Zealand Super Alpha
• New Zealand Green Bullet
• Horizon
• Newport
• Warrior
Hops for bittering (harsh)
• Columbus
• Chinook
• Galena
• New Zealand Pacific Gem
• Millenium
Dual purpose hops
• New Zealand Cascade
• Centennial
• Amarillo
• Northern Brewer
• Perle
• Ahtanum
• Cluster
Hops for aroma
• Cascade
• Mt. Hood
• Crystal
• Saaz
• Fuggle
• Simcoe
• Columbus
• Palisade
• Glacier
• New Zealand Riwaka
Hops for dry hopping
• Any hop that has a pleasant, resiny aroma.
Hop Resources
• www.freshops.com
• www.hopsdirect.com
• www.hopunion.com
• www.oregonhops.org
• www.realbeer.com/hops
• www.nzhops.co.nz