Hop Pairing & Substitution
When the esteemed editorial staff of BYO suggested the topic of pairing hops and hop substitution, I thought it would be an interesting one to write about. Then I sat down to write it and realized it was actually something of a minefield instead. That is because it involves talking about things like flavors and aromas, and perceptions of these are very personal — so my suggestions might not be acceptable to other brewers, experienced or not. For example, Cascade was the predominant hop used by home and craft brewers in pale ales and IPAs in the 1980s and 1990s. This variety was used in some very good beers, yet one acquaintance of mine would not touch Cascades because he just didn’t like the flavor at all. And another good friend wouldn’t touch this hop, simply because when he started brewing commercially everybody else was using it and he wanted to be different.
Given these comments, I considered it would be best to lay out some guidelines as to how to pair or substitute hop varieties, rather than to give a long list of specific suggestions, although there will of course be some examples. Under pairing, I am only going to deal with hops added for flavor and aroma, not those used for bittering. For the latter, many brewers simply take the option of using the highest alpha acid variety they have in order to reduce the amount of trub at the end of the boil. This approach assumes that hops boiled for 60-90 minutes have no effect on flavor or aroma so that pairing of bittering hops is an unnecessary procedure. Note that there are arguments against this statement, such as that some hop varieties yield a cleaner, sharper bitterness than others, and that first wort hopping affects hop flavor in the beer — but I shall not deal with these effects here.
Hop pairing
My first comment here is one that I have admonished brewers to do before, and that is to ask yourself exactly what sort of beer you are brewing. Quite obviously, it has to be a style in which hop flavor and aroma are important, so we are not talking about beers like porters and dry stouts, saisons, or any of those various Belgian-derived beers where yeast flavors are the most important taste characteristics. Mostly that leaves pale ales and the various forms of IPA to be considered as most suitable for this approach, although it would also work for a Czech-type Pilsner. I am not suggesting that you cannot add hops for flavor and aroma to any brew you fancy; indeed it is your beer and you can do what you want, and you may well want to experiment with unusual combinations and develop your own take on any given style. If you do try something on these lines, such as aiming to brew a brown ale with a lot of hop aroma; however, I would suggest that your first approach to such an experiment should be with only a single hop variety. If the result is pleasing to you, then you can consider using two or more varieties in subsequent brews.
Once you have sorted out what kind of beer you aim to brew, you must then ask yourself why you want to use a combination of hop varieties. Is there a variety with a character you like, but can be a little too intense when used alone? As I indicated earlier, some people do not find Cascades entirely to their taste and may want to mute its effect by pairing it with a milder hop, such as Fuggles, Saaz, Liberty or Mt. Hood. Note that if you do this you need to replace some of the Cascades (50% seems like a good number) with your chosen alternative, rather than keeping the original amount of Cascade and adding the same amount of the second hop. In the latter case the Cascade may continue to dominate the flavor and aroma and you will have wasted your time adding a second variety.
The second option for pairing is where you want to get a spectrum of hop character, say where you have found two or three varieties work well individually with a particular beer and you want to see how they work in combination with each other. I would suggest three rules to follow in this case, the first being that you do not want to use too many varieties, or you can actually get a “muddy” effect on the palate and in the nose — a sort of olfactory overload! Two to three varieties is good but 15 is certainly over the top! Rule two, concomitant with the first, as indicated before, do not overdo the amount of hops added. If, say, your original recipe calls for 1 oz. (28 g) of finishing hops, and you want to replace that with three varieties instead of one, use ⅓ 1⁄3 – 1⁄2 oz. (9–14 g) of each, not 1 oz. (28 g) of each. Note that this implies that you must have a scale capable of accurately weighing amounts of less than an ounce; in fact I would recommend that you have such a scale whether you are pairing hops or not! The third is that the chosen hops should have similar characteristics — they should complement each other. If the effects of one hop variety dominate the beer then you have lost the
point of the exercise. That means that you should choose varieties with similar types of aroma/flavor characters.
An obvious bad example would be to use a combination of a hop yielding mild, gentle aromas (such as Magnum) with one with more powerful and definitive character (such as Citra®).
To amplify the third rule, let’s say you are brewing a beer where hop flavor and aroma are background aspects of the beer’s palate. Then you might get optimum results with a mildly spicy hop such as Hallertauer paired with a Hallertauer derivative such as Liberty or Mt. Hood, or with the mild English varieties such as Goldings, Fuggles, First Gold, or Target. If you want your beer to have a little more intensity of hop character, then you could consider, say, a mixture of Nugget and Northern Brewer or Willamette. If you are looking at achieving even more intensity in this respect then you would probably want to go with combinations of the various types that give strong citrus flavors and aromas. These obviously include Cascade, Centennial, Citra®, Simcoe®, and Amarillo®, but you could also include “piney” types, such as Chinook. In this case, you do not have to do the mixing yourself, for you can buy blends of such hops, specially designed to complement one another under the trademark name of Falconer’s Flight® from Hop Union. Note that in this paragraph I have not offered any recommendations as to which beer styles these hop combinations should go with — remember that I said earlier you must decide exactly what you want to achieve with your beer before deciding upon which hop combination will work for it.
Hop substitution
Here we are looking at something completely different than hop pairing, either because you cannot obtain or do not have a variety called for in a recipe, or because you want to try out a different variety to see how you like it.
In other words, you are looking to use a different variety to give an identical or at least closely similar result. Again I am not going to give a list of appropriate substitutions but will rather try to explain the philosophy behind the procedure. If you want a comprehensive list, then check out the online hop chart in our resource area. In the case of bittering hops, your approach should be quite simple — use another hop with pretty much the same alpha acid content as the “original.” That way you won’t noticeably change the IBU level of the beer. If you use a hop with different alpha acid content you will need to adjust the amount in order to maintain the same IBU level. You do not need to do a fancy calculation, just pro-rate it:
Weight of new hop = weight of original hop x (alpha of original hop/alpha of new hop).
So, if the original was 1.5 oz. (42.5g) at 7.2% alpha, and the new one is only 4.5% alpha; then:
Wt. of new hop = 1.5 x (7.2/4.5) = 2.4 oz. (68 g)
That means you can make your substitution without knowing the IBU level of the beer, (but if you don’t know it then shame on you, because you should know it!). As far as flavor goes, you should generally substitute the original with a variety known (preferably from your own experience) to give a clean bitterness.
Substitution is a little trickier when it comes to flavor and aroma. Your first approach should be to check out the characteristics of the original and try to match them with the new variety. If you know the composition of the oils in the hops in question just look for a match, especially in levels of co-humulone. But you probably will not have access to that information, so a second approach would be to look carefully at the descriptors given by your supplier and see if you have a reasonable match. If both hops are described as giving mildly spicy aromas that’s a fine substitute. Similarly if both are said to give citrus aromas, although be careful as not all citrus is equal! The hop chart on byo.com is useful for this as it not only gives descriptors for a wide range of varieties, but it also offers suggested substitutes.
One way of looking at that is to say that you should replace one English variety with another English variety, or to substitute one citrus Northwest hop with another. Or, at the other extreme, substituting an intense citrus hop like Amarillo® for the much milder Styrian Goldings is going to give your beer a very different palate. But this is a very simple approach, because, for example UK Fuggle can be nicely substituted by US Willamette (itself a Fuggle derivative).
Another very simple approach is to actually smell the hops you are using. Take the time-honored approach of breaking up a pellet of each by rubbing it vigorously on the palm of your hand and then comparing the two by smell. It is a bit of a hit or miss method depending upon the accuracy of your nose, but it does have the advantage of dealing directly with the actual samples you have, and thus accounting for when and where they were collected and how they have been stored.
You may even already have the answer from your own brewing records. Check back and see if you have made beers similar to the one you wish to brew now, and what hops you used in them and what flavors they conferred upon the beers. With any luck you will find enough clues in your notes to tell you which are the best substitutes for the original hop in the recipe. You do keep detailed notes don’t you? If you don’t, then this is a good reason to do so in the future.
It should also be obvious that when substituting flavor and aroma hops you should make additions at the same time in the boil and/or post boil as in the original, and should use the same quantities as before. Also, I have not said anything about dry-hopping in the fermenter or keg. In fact, that’s because most of the comments above also apply to dry-hopping, even though the flavors and aromas obtained in this way may be very different from those obtained by the various forms of late hopping.
Finale
Hop pairing and substitution are complex issues and depend very much upon personal taste. But if you think about it carefully, follow the guidelines above, and match them with your experience, you should be able to safely navigate this minefield. If you make a change, in either pairing or substitution, and the beer does not quite turn out the way you expected it to, don’t be disappointed — always judge it by whether it is a good beer or not. Also, keep in mind that to the scientist there is no such thing as a failed experiment; they all teach us something!
