So far, this series has focused on what goes into beer. Now it’s time to start digging into how we use those building blocks. The first ingredient we tackled was hops, so it makes the most sense to start there.
Before we dive into the steps, let’s talk briefly about hops. They have alpha and beta acids, which contribute bitterness, and they contain a complex mix of volatile aromatic oils that provide the flavor and aroma we all love. Getting all of those components into your beer can be a little tricky because of a fundamental conflict. It takes time in the boil kettle to convert the alpha acids into their isomerized bitter form. But every minute of that time drives off and breaks down some of the aromatic oils. The traditional three hops-addition steps are a compromise that balances this trade-off.
The first addition goes all in for Team Bitter. These hops are added early in the boil, spending the most time in the kettle, usually 60 minutes or more. That allows plenty of opportunity for the alpha acids (e.g., humulone, cohumulone, and adhumulone) to go into solution and be chemically converted into their bitter form. Of course, that’s also long enough to boil off the volatile hops oils and lose most of the flavor and aromatics that these hops might have provided.
The flavor-hops addition is generally made about 20–30 minutes before the end of the boil in an attempt to find a midpoint along the bitter-to-hoppy continuum. This addition will still extract some bitterness, but the important thing is what happens to the aromatics. The most volatile aromatics will be driven off, but there are plenty of flavorful compounds that can withstand the heat and lend some hoppy character.
The final aromatic addition is made either in the last few minutes of the boil or at flameout. Assuming the wort is immediately chilled, this doesn’t allow much time for isomerization, and there’s less opportunity to evaporate off hops essential oils. The net result is that very little bitterness is added, but many of the pleasant aromatics remain. As you may know from experience, the exact timing can make a big difference to the intensity and character of the beer’s aroma.
In the interest of better understanding that spectrum of bitterness fading over to delightful hops flavor and aroma, we’re going to sample a few isolated points and contrast them. We’ll start with a base pale-ale recipe, brewing a control batch that follows the full tradition of three hops additions. Then we’ll create a set of beers that will each have a single hops addition at various points during the boil.
Volume (after boil): 1 gallon (3.8 liters)
IBUs: 43 (control batch)
Grain: 1.25 lb (567 g) light dry-malt extract; 4 oz (113 g) crystal malt (30L)
Hops: 0.125 oz (3.5 g) Amarillo [8.6% AA] at 60 minutes; 0.125 oz (3.5 g) Amarillo [8.6% AA] at 30 minutes; 0.125 oz (3.5 g) Amarillo [8.6% AA] at 5 minutes. (If you need to substitute a different hop, aim for about 40 IBUs in a one-gallon/3.8 l batch.)
Yeast: ½ packet SafAle US-05
Process Steps for Control Batch
Dissolve the DME into the initial volume of water (1 gal/3.8 l plus any make-up for the evaporation loss), then bring to a boil. Start the boil, then add the first hops addition. After 30 minutes, stir in the second hops addition. After another 25 minutes, add the final addition of hops. Let the wort boil for 5 minutes longer.
Chill the wort down to pitching temperature (use a cold-water bath or immersion chiller). Transfer to a gallon jug and pitch the yeast. After a week or so, rack the beer off the hops and bottle it with about 0.8 oz (23 g) total dissolved priming sugar.
The four experimental batches should follow the same recipe and process as above, except each will have only a single hops addition: one batch will have 60 minutes of boiling with hops; another will have 30 minutes; another 5 minutes, and the last batch will have 0 minutes of boiling with hops (take the pot off the burner and add the hops).
You’ll have five batches to compare. In this case, the control batch is there to give the full profile of hops contributions. The four experimental batches won’t be complete enough to make a great beer, but you will be able to isolate what each addition brings.
Start with the control batch. If you used the recommended Amarillo hops, note the citrus and floral character in the aroma and the flavor. The bitterness should be balanced by a reasonable level of malt. Once you’ve grasped the specifics of smell and taste, pay particular attention to the flow of sensory impressions and how they combine.
When you have a handle on the control beer, pour samples of the 0- and 5-minute batches. Contrast the hops aroma of each. Do you notice a difference in intensity or character? You would expect the 0-minute version to have a slightly stronger and more intriguing nose than the 5-minute one. It’s also interesting to compare these aroma experimental batches to the control batch. Even though the control batch had the same aroma addition as the 5-minute batch, they likely don’t smell quite the same because the flavor addition still contributes some aroma, which you’ll notice later.
Now try a sip of each of the two experimental batches. Of course, each will lack the bitterness of the control batch, but the 5-minute version should be noticeably more bitter than the 0-minute one. In both cases, some isomerization occurs before the batch is chilled, but the extra 5 minutes does make a difference. You’ll also notice some hops flavor, although it may well be overwhelmed by the malt.
Now, open the 30-minute batch. A good sniff will reveal what the flavor-hops addition contributes to the final aroma. It will be milder and more simplistic, but you should still get some of that citrus character. When you taste this one, the hops flavor should stand out more, and there should be significantly more bitterness than in the aroma versions.
The 60-minute batch shifts the focus more fully to the bitter side. You may detect a faint hops aroma—I sensed a little bit, but it was indistinct and generic. The taste will be somewhat more bitter than that of the 30-minute batch, but it won’t offer much flavor-hops character. Take a moment to compare the bitterness between the 60-minute and 30-minute versions. They’re closer to one another than you might have guessed because 30 minutes offers plenty of time for hops isomerization.
Now that all five beers are poured, compare each one in turn with the control batch again. You’ll likely notice that the control batch is more than just the sum of the parts; the multiple additions work in concert to create a smooth flow from the initial sniff into the first hit of hops flavor and bitterness and then into the finish that settles into a clean bitter base with a lingering hint of orange flavor.
Lessons Learned and Other Possibilities
One good takeaway from this experiment comes from the comparison of the 30- and 60-minute versions. Given that the bitterness is not so different, it suggests that you could experiment with a hopping schedule with only two additions: one for bitterness and flavor at 30 minutes and a second for aroma. It would be worthwhile to run another mini-batch like this to see how it compares to the control. Just use a little more than two times the flavor hops (maybe 8 grams rather than a total of 7 grams), and you’ll get about the same total level of bitterness with a stronger hops flavor.
It’s also interesting to think about how the three standard additions work in concert and then consider continuous hops additions, as in Dogfish Head’s 60 Minute IPA. That’s certainly worthy of an experiment, but the amounts work out to be a bit small for one-gallon batches. If you want to try that out, I’d recommend committing to at least a standard five-gallon (19 l) batch.
Photo: Matt Graves/mgravesphoto.com