DRY HOP TEMPERATURE: WARM VS. COOL

#brewbossbrewing Brew Boss Electric Homebrew Equipment www.brew-boss.com

Author: Ray Found

IPA is one of the most popular styles of craft beer, one in which I’ve invested a lot of effort over the last year in my plight to develop my version of the perfect #IPA. This is exactly what MACC IPA is to me, a recipe I’ve tweaked multiple times that I’m finally happy to call complete. When it comes to IPA, many interesting variables to test come to mind, but none more on the forefront than those that might bring greater understanding to one of the quintessential components of this delicious style: dry hopping.

We’ve explored #dryhop quantities, dry hop length, double dry hopping, and the impact of pellet and whole cone in the dry hop, but we’ve yet to investigate the temperature at which hops are added to the fermented beer. It seems the most commonly practiced method involves adding the hops to the beer at fermentation temperature with many performing a cold crash a few days later. However, we recently heard from a reader who claimed to be getting great dry hop character despite adding the hops to the cold beer post-cold crashing. Huh. While I’ve heard of keg hopping, which involves leaving a charge of hops suspended in a cold keg while serving, I’d never given much thought to the temperature question. Until now.

| PURPOSE |

To evaluate the differences between 2 beers of the same exact recipe where one was dry hopped warm (76°F) and the other cold (36°F).

| METHOD |

As any regular reader of Brülosophy is perhaps aware, I’ve used my MACC IPA recipe in quite a few xBmts, I love this beer. Given the variable being investigated here, I thought it a perfect fit. Having pretty much settled on a final recipe, one that has scored well in BJCP-ranked competitions and is always well received by my hophead family and friends, I’m excited to announce it is the second recipe kit being released in collaboration with our friends at Love2Brew! For anyone looking for a drinkable and deliciously hop-forward IPA, I trust this kit will get you where you want to go, it’s available right now!

Failing to account for my lack of WLP090 San Diego Super Yeast, I decided to ferment this batch with Safale US-05, a benefit being I didn’t need to make a starter ahead of time. My brew day began by heating the strike water, during which I collected and milled my grains.



With the strike water to temp, I mashed in and set the timer to 1 hour, stirring a couple times throughout.



With the uneventful mash complete, I collected the first runnings, performed a quick batch sparge, then hit the flame under the kettle. The boil started off very boring, receiving nothing but a few drops of FermCap-S until the last 20 minutes when the first and only dose of boil hops was tossed in. At the conclusion of the boil, I added the large charge of flameout hops and allowed them to steep for 20 minutes before proceeding to quickly chill the wort.





I evenly split the wort between 2 carboys and placed them in my chamber to finishing chilling to my target fermentation temperature. The following morning, I rehydrated and pitched a pack of US-05 into each fermentor. Signs of fermentation were visible within hours and became quite vigorous the following day.





About a week later, both beers appearing finished fermenting and sitting at 1.013 SG, it was time for the fun to begin. One of the fermentors was removed from the fermentation chamber and allowed to sit at 74°F/23°C, while the other carboy was cold crashed to 34°F/1°C. Once the temperature of the cold crashed beer stabilized, identical portions of hops were added to both fermentors and they were left alone for 4 days. While I typically cold crash andfine with gelatin in primary a few days after adding the dry hops, in order to avoid introducing extraneous variables, I opted to keg both beers at the temperature they were dry hopped at, which meant fining would occur in the keg once both were cool. Oh, the sacrifices we make for beer science. The warm dry hopped beer was a complete headache to keg, with extensive hop matter floating about that clogged my siphon multiple times. Regardless of the results, I vow never to keg a dry hopped beer without first cold crashing again, such a pain. The fluffy nature of the trub at the bottom of the warm dry hopped batch increased my yield loss, resulting in about 3 quarts less total beer in the keg. Dammit!




Left: warm dry hopped | Right: cold dry hopped

Once packaged, both kegs were purged and hit with CO2 to seat the lids, then they were disconnected from the gas so as to avoid any carbonation differences due to beer temperature. Once the temperature of each keg was stable, I added gelatin to each then cranked up the CO2 to carbonate. By the following weekend, the gelatin had done its thing and the beers were looking great.




| RESULTS |

All told, 16 people participated in this xBmt including craft beer loving family, friends, and members of my homebrew club. Each taster was served two samples of the warm dry hopped beer and one sample of the cold dry hopped beer in opaque colored cups then asked to identify the odd-one-out. While 9 correct response (p<0.05) would be required to suggest a significant difference, a total of 10 tasters (p=0.007) correctly identified the different beer, suggesting these participants were reliably able to distinguish between beers dry hopped at drastically different temps.

Of the 10 correct respondents, 3 reported preferring the cool dry hopped beer, 5 said the liked the warm dry hopped beer better, and 2 had no clear preference despite noting the beers as being different.

Interestingly, 7 of the 10 correctly identified the beer of the two was dryhopped warm and which was dryhopped cool.

My Impressions: My personal experience was represented well by the tasting panel in that I was able to tell the beers apart with decent consistency, though it was by no means trivially easy. I noted greater aromatic intensity in the warm dry hopped beer with a more pungent fruity note. In fact, it was similar to the difference in aroma I notice when I pour myself a cold IPA and it warms over time. The flavor was a similar story, I thought the cold dry hopped beer was slightly smoother and less intensely hoppy, while the warm dry hopped beer exhibited a bit more hop bite or sharpness, though it didn’t come across as harsh.

I absolutely love this beer and have honed the recipe over the course of a year that included 8 batches, each with only minor adjustments. It could be my personal bias and preference for the familiar talking, but I preferred the warm dry hopped beer , I felt it possessed the sharp fruit punch of hops I enjoy so much. It smells and tastes like MACC IPA is supposed to smell and taste! 

 
| DISCUSSION |

Frankly, I’ve no inclination to dry hop with the exact processes used on this batch again. Adding the dry hop charge to cold beer failed to extract enough of the really bright hop aroma I prefer, and while I felt the warm dry hopped batch was great, kegging prior to cold crashing was a pain in the ass. I’m inclined to continue dry hopping warm and cold crashing in the fermentor because it works well for me. But for whose process is different than mine, dry hopping cold is certainly a valid option, as that beer maintained totally adequate levels of aroma and flavor.

These results may not have motivated a change in my process, but it definitely got my gears turning. I wonder how dry hopping warm then immediately cooling the beer would impact the final product? And while I’ve no interest in performing it myself, I would like to know more about the impact of cold crashing when the dry hops are added at the same time and temperature. And the list continues to grow!

http://brulosophy.com/2016/01/18/dry-hop-temperature-warm-vs-cool-exbeeriment-results/

Homebrewing: How to Dry Hop Your Beer

Opening a sealed package of hops from the homebrew store gives a blast of that fresh aroma that sometimes seems to be difficult to capture in a beer. The truth is, the simple technique of dry hopping is all it takes to bring out those wonderfully fresh citrus, pine and earthy aromas in your homebrew.

Dry hopping is basically the ultimate late hop addition.

Traditional boiling changes the natural alpha acids in hops into iso-alpha acids—they're the stable compound that provides the bitter flavors in beer. Unfortunately, boiling also breaks down the volatile essential oils that comprise the aromas and much of the flavor of the hop itself. When we first talked about hops, I mentioned that the later the hops are added to the boil, the more they will affect flavor and aroma. This is because the less time hops are boiled, the fewer bitter iso-alpha acids are produced and the fewer aromatic essential oils are driven away. Dry hopping is basically the ultimate late hop addition. 

The phrase is a bit of a misnomer, since you don't keep the hops dry at all. Instead they are added to the beer in the conditioning phase, after the fermentation but before it's time to bottle. Usually this means you'll add the hops after the airlock has stopped bubbling. If you're doing a two-stage fermentation, then the dry hops would be added at the time you transfer your beer to a secondary fermentation vessel. Otherwise the rapid discharge of carbon dioxide will "scrub" the delicate flavors that we're trying to preserve. Since the beer is only around 65°F at this point in the process, the breakdown of essential oils occurs much more slowly, preserving the flavor and aromas of the hops.

Dry hopping is a great way to experiment with different recipes. You can always dry hop a Pale Ale or an IPA with the same variety of hops used in the recipe. Or you can try to find a variety that complements the flavors you're already using. In our Pale Ale, for example, dry hopping with the citrusy Amarillo hops would help bring out the grapefruit character of the Cascades added late in the boil. But you can also try dry hopping other, more unexpected styles to make a hoppy American-style Stout or a hoppy wheat beer.

When you do dry hop a homebrew, you'll want to drink it a little quicker than usual. The added aromas are still quite volatile, even at cooler temperatures, and they will dissipate within a few months of bottling. Some lasting flavors and aromas will remain after that, but you will notice that the first few bottles you open will have a much stronger aroma than the last ones in the batch.

Dry Hopping Instructions

The only equipment needed is a nylon hop bag, a few clean glass marbles, and about an ounce of hops. The job of the marbles is to sink the bag of hops to the bottom of the carboy or fermentation bucket. You can use as much as two ounces of hops for a five gallon batch, but one is enough to get the job done.

Sanitation is still important here, but since we add the hops after fermentation is complete, the alcohol present in the beer provides some protection against unwanted bacteria. Simply boil the hop bag and the marbles for about 10 minutes to sanitize. Hops are naturally antiseptic, which is one of the reasons they're used in the brewing process to begin with, so there is no reason to sanitize them. Now, just add the marbles and the hops to the bag, and put them in the fermentation vessel.

The majority of the benefits will occur within a week, but you can leave the dry hops in the fermenting vessel up to two weeks if you would like. After that, just transfer to a bottling bucket and bottle as usual.

http://drinks.seriouseats.com/2011/03/homebrewing-tips-how-to-dry-hop-your-beer-what-is-dry-hopping.html