I brew often, sometimes when I’ve got plenty of beer on-hand, mainly because I enjoy it. Usually I make two 5 gallon batches in a single brew day, though I have the capacity to make up to two 10 gallon batches. However, I’ve said before that I sometimes miss that feeling of novelty I used to experience when I first started. In order to combat this and spice things up a bit, I’ve decided to dedicate a portion of my brew days to performing exBEERiments, informal and arguably anecdotal experiments designed to test, support, and potentially debunk certain homebrewing ideas. Some of these exBEERiments may have little to do with actual beer, such as my comparison of different glass cleansers, while others will be how certain process differences impact the same beer. In the case of the latter, my plan is to have a panel of tasters including BJCP judges and dedicated homebrewers, sample the beers blindly and give their critique. In most cases, these tasters won’t know what the exBEERiment is about, they will simply be provided multiple samples and asked to take notes on their experience with the beers. Once this data is collected, I will then share it here, hopefully giving back in some small way to this very cool community.
Thanks to all the rad folks over at r/homebrewing who suggested many of the following ideas, you guys got very creative and gave me plenty to think about! Here is a pretty exhaustive list of ideas and my thoughts about how to approach each. Please, if you have any questions or suggestions on how to improve an exBEERiment, do not hesitate to leave a comment!
Primary-only vs. Transfer to a Secondary Vessel
An age-old debate fraught with passionate opinions by people on both sides. There are those who religiously transfer to secondary, convinced it improves flavor and produces a clearer beer, while others swear this is an outdated and potentially risky process that should be relegated to the annals of homebrewing history. I’m certainly in the latter camp and have been pretty vocal about this opinion. While I’ve done it both ways, I thought it would interesting and fun to test any differences in a slightly more controlled fashion.
The Plan: I’ll make a single batch of wort, either 5 or 10 gallons, and split it into 2 carboys, pitching the same yeast at the same exact rate and fermented right next to each other at the same temperature. After 4-5 days, one of the beers will be transferred to a second carboy while the other will remain in the primary. Both beers will then be kegged a week or so later. After 7-10 days in the keg, basically once carbonation is stable and the beers have had time to drop bright, I’ll ask a panel of tasters to compare the 2 beers, paying special attention to any differences in flavor, aroma, and clarity. I’m thinking a simple APA or IPA will be a good beer for this exBEERiment, as I am also interested in the differences between beers dry-hopped in primary vs. secondary. This should be a fun one.
Hot-Side Aeration: Myth of Fact?
When I first started brewing, I was told that all transfers pre-chilling of the wort should be done with caution and ease, as any aeration could produce off-flavors in the finished beer. One LHBS worker said this is where beers can pick-up a metallic flavor, certainly nothing I wanted in my beer. As I honed my process, read more about brewing science, and listened to podcasts about brewing, it became clear to me HSA was less a matter of fact and more a product of fear. I began worrying less about splashing my wort and I’ve noticed no difference, but I’m curious if 2 of the same beers side-by-side, one treated gently and the other beat to holy hell, will be any different.
The Plan: Make two 5 gallon batches of the same exact beer. One batch will be treated very gently from mash through the end of the boil, the other batch will be massively aerated at every step of the process until the yeast is pitched including during the mash, during the transfer from the MLT to the kettle, and throughout the boil. This will be accomplished with a 24″ whisk. Both beers will be treated the same after the yeast is pitched.
Impact of a Shorter Boil on the Presence of Dimethyl Sulfide (DMS)
It’s commonly accepted practice to perform a 90 minute boil when a large proportion of the grist is Pilsner malt, the reasoning being to reduce the production of DMS in the boiling wort. Some brewers have opted to use a 90 minute boil for all the beer they make, just to be safe, as DMS can cause a beer to have a cooked vegetable/creamed corn aroma and flavor, even at fairly low levels. This is definitely something we don’t want in our beer. Briefly, Pilsner malts have a higher SMM (S-Methyl Methionine) content than other base malts, this SMM is essentially turned into DMS during the boil, hence a longer boil allows more time for the DMS to be driven out of the wort. I’m curious if there will be any demonstrable differences between 2 beers, both made with 100% Pils malt, one boiled for 90 minutes and the other for 60 minutes.
The Plan: Make two 5 gallon batches of the same beer, both using 100% Bohemian Pilsner malt as the grist, hopped only moderately, and fermented with WLP029 at 58°F. One batch will be boiled for 90 minutes, the other boiled for only 60 minutes, after which they will be treated exactly the same until sampled by a panel of tasters.
First Wort Hop (FWH) vs 60 Minute Bittering Addition
FWH is when a portion of hops are placed in the kettle prior to adding any wort. The wort is then added to the kettle and the hops remain the entire duration. I believe it was Randy Mosher who I heard say in an interview that this method produces a softer, less harsh bitterness. I heard from somewhere else that it could even impart certain desirable flavor and aroma compounds that stick around longer than beers with just late hops. For those who listen to the Brewing Network as incessantly as me, you’ve probably heard Jamil Zainasheff pontificate on how his experience with FWH beers is that the bitterness is actually more harsh, thus he recommends sticking to a standard routine of adding hops to the boil. I’ve use the FWH method and the beers were good.
The Plan: Design a 5 gallon batch of Pale Ale using a single hop, probably CTZ or Simcoe. Using BeerSmith, calculate the amount of hops needed to achieve 25 IBU at both 60 minutes and FWH. Split 5 gallons of wort into 2 kettles, one receiving a FWH and the other a typical 60 minute addition, both predicted to achieve the same IBU. All other hops will be added at the same time, perhaps just a big dose at flameout. Ferment, package, and compare.
All Hops at Flameout/Whirlpool
Craft brewers have large kettles that take a while to drain. During this process, a whirlpool is created in the kettle that basically forces particulates (hop matter, protein, etc) into a cone at the bottom of the kettle. Many breweries use this as an opportunity to add more hops to the wort, significantly increasing hop aroma in the finished beer, something many of us desire. Of late, I’ve heard of some breweries adding hops only during this stage, completely eliminating all hop additions during the boil. It’s been said that this is roughly equivalent to a 20 minute addition on a homebrew scale, though there appear to be some slight differences, namely the hops in the craft brewer’s kettle is no longer boiling and gradually reducing in temperature while the hops are added. The hop stand idea has been getting quite a bit of talk lately and I’ve actually used it a few time, rather successfully in my opinion. But those beers were all hopped during the boil as well. The question remains: how would a beer with 100% of the hops being added at flameout and left to steep turn out?
The Plan: Brew a 5 gallon batch, maybe something like a Pale or even Amber Ale, throw a shit ton of hops it at flameout, enough to get me to about 35 IBU per BeerSmith, and allow them to steep for 20-30 minutes. Ferment with either WLP090 or my “UK Blend” (WLP002 + WLP013), package, and evaluate with friends.
The Impact of Yeast Pitching Rate
The brewer makes the wort, the yeast make the beer. In my experience, yeast is the absolute most important factor in making good beer. Most of us know about the importance of pitching adequate amounts of healthy yeast, though there are many who continue to report making good beer using much less yeast than our calculators suggest. In fact, I’d guess the first batch nearly all of us made was done without a starter or even a concern about pitching rates, and the beer was at least good enough to keep us coming back for more. But underpitching isn’t the only concern. What would the impact be on a beer pitched with too much yeast?
The Plan: Brew 6 gallons of wort and split it into 3 carboys. Determine the appropriate pitch rate for 2 gallons (I like Yeast Calculator) using a dry yeast, probably Nottingham. One carboy will receive the appropriate amount, one will receive 3x more than the appropriate amount, and one will receive 3x less than the appropriate amount. While I rarely use dry yeast, I believe it will be easier to use for this exBEERiment than liquid due to the fact it can be weighed. Ferment each beer together at the same temp, documenting for each the lag from pitch to active fermentation, the apparent vigor of fermentation, how long to reach FG, and of course any flavor differences in the finished product.
Difference Between Dry Yeast Pitched Dry vs. Rehydrated
Dry yeast these days is apparently of a much higher quality than it was “back in the day.” While I still prefer liquid, I have used dry many times and it has always worked fine. The brewers I know who prefer dry yeast appreciate the fact it is less expensive and comes packaged with enough cells for most standard beers, negating the need for a starter. While most dry yeast packages I’ve seen instruct users to sprinkle the yeast directly onto the chilled wort, talk of rehydrating the yeast before pitching has been increasing steadily, with many experts suggesting the sprinkle method results in significantly less viable cells in the beer.
The Plan: Split a 10 gallon batch into two carboys, sprinkle dry yeast in one and pitch rehydrated yeast in the other. I’ll document lag times, fermentation vigor, time to FG, and any perceptible flavor differences.
The Impact of Fermentation Temperature
One of the most oft given pieces of homebrewing advice: control your fermentation temperature. And rightfully so. High temps produce unwanted esters and fusel alcohols, lower temps can cause the yeast to stall and drop out, while the proper temperature produces a clean and delicious beer. What’s fascinating to me is that the different between “too cool” and “too warm” is often only about 10°F.
The Plan: Split a 5 gallon batch of wort into 2 carboys. Using my favorite US strain, WLP090, control the fermentation temp on one batch to 66° (090’s sweet spot) and leave the other in my closet, which is usually about 72°, meaning the fermenting wort could get as warm as 80°.
Immediate Chill vs. No-Chill Method
I was taught that it is important to chill your wort as quickly as possible once the boil is over, primarily to achieve a good cold break, which supposedly results in clearer beer. Well, leave it to those rogue Aussies, what with their simple Brew-In-A-Bag technique and all, to snub their noses at our brewing traditions by coming up with the seemingly crazy idea of transferring near-boiling wort into plastic jugs and allowing them to cool naturally, usually overnight, before pitching yeast. The neat thing is, it seems to work just fine. In fact, these brilliant bloaks are making all-grain brewing much easier for beginners to get into. Cheers to you, Australia!
The Plan: Brew 5 gallons of beer. Prior to chilling, rack half off into a proper container, seal it, and place it in the fermentation chamber controlled to 66°; chill the other half to 66°, rack to carboy, and place in the same chamber. I’m thinking it’d be best to pitch the yeast into each at the same time, so I can more accurately monitor any differences in fermentation, as well as avoid the problem of exothermic heat created from the chilled batch from tripping my regulator to run the freezer while the no-chill batch still has no yeast in it. Thoughts?
The Impact of Wort Clarity on Ultimate Beer Clarity
Some brewers seem to stress, perhaps excessively, about transferring only the clearest of wort to their carboys, using numerous gadgets to keep as much trub as they can out of their fermenting beer. I used to be guilty of this, admittedly, though I’ve loosened up quite a bit after an experience where I was rushed and didn’t have time to let the trub settle before sending it to the fermenter. Interestingly, that beer was just as clear, maybe even more clear, than other beers I’d made. Is there something about having some hop matter and protein break in the fermenter that actually contributes to a brighter finished beer?
The Plan: Brew 10 gallons and fill one carboy with trub-rich wort, then let the trub settle out before filling the next carboy. Ferment both with the same yeast at the same temperature, documenting all elements of the fermentation as well as finished flavor and clarity.
The Impact of Mash Temperature
I tend to mash to mash the large majority of my beers between 150° and 156°, only occasionally going lower or higher for specific styles. John Palmer does a great job of describing the science behind how alpha- and beta-amylase are a function of mash temperature. To put it simply, lower mash temps apparently produce a more fermentable wort, which can lead to thinner body and mouthfeel, while higher mash temps produce a less fermentable wort, contributing to increased body.
The Plan: Make two 5 gallon batches of the same recipe, mash one at 145° and the other at 165°, evaluate any differences in OG, FG, fermentation, and general characteristics of the finished beer.
How Growing Region Effects Hop Characteristics
This exBEERiment was recommended by a Reddit user and I thought it was cool idea. He was curious how hops of the same variety differ in characteristic based on the region they’re grown in. One of my favorite hop varieties are domestically grown Fuggles, a hop that is originally from the UK and continues to be grown heavily there. There are also many American hop varieties that stemmed from German noble hops, such as Mt. Hood, which came from the Hallertau hop. Are there significant differences?
The Plan: Split a 10 gallon batch of wort into 2 kettles, each kettle getting the same amount of a single hop grown in different regions. I’ll likely make a lighter beer using WLP029 to ferment it with and compare Mt. Hood to Hallertau, just because I’m pretty sure I’d want to drink 10 gallons of both.
The Impact of Boil Time on All Late-Hopped Ale
For many, a brew day can last anywhere from 4-8 hours, taking up a significant chunk of one’s day. This may be very enjoyable to some, but many brewers (and their significant others) wouldn’t mine shaving a little time off of the day. I’ve heard of people brewing 15 minute extract beers successfully, but it seems the 60 minute boil is a hard-set rule, the main contention to shortening the boil being concern over potential DMS production. I’m curious if anyone has ever actually tried a shorter boil.
The Plan: Split a 6 gallon batch of wort into 2 kettles with more going into the regular boil kettle to account for boiloff. All hops will be added at 15 minutes and less left to flameout then both batches will be pitched with the same yeast and fermented similarly before packaging.
These are just some of the more interesting exBEERiments I hope to perform over the next year or so, though I received quite a few suggestions that will definitely receive consideration:
– Compare multiple yeast strains from similar regions (UK, US, etc)
– Decoction vs. non-decoction vs melanoidin malt
– Step mash vs. single infusion
– Compare wort boiled indoors to wort boiled in the sun outdoors for skunkiness
– Cacao nibs vs. cocoa powder
– Reusing sour yeast cake, how much longer to sour beer, flavor differences
– Malt substutions (i.e., 2-row + Victory = MO; 3:1 carafa II:black patent = carafa III )
Again, thanks to everyone who contributed, I’ll be sure to post about each exBEERiment as I complete them. Hopefully we all learn something interesting!
11 thoughts on “Ideas for upcoming exBEERiments”
Recently found your blog and have read through the older posts – thanks for taking the time to put out good information like this!
Really looking forward these ExBEERiments, especially:
Impact of a Shorter Boil on the Presence of Dimethyl Sulfide (DMS)
Immediate Chill vs. No-Chill Method
The Impact of Mash Temperature
Thanks, man, I’m glad you found it! I hope to get to some of the exBEERiments soon.
I enjoy reading the results of your experiments. Thank you for taking the time to research these topics. You seem to have some great ones on deck. Another idea would involve, “does squeezing the bag matter?” This could be either a brew in a bag or a extract with specialty grains experiment.
Great idea! Added to list.
Aeration vs. no aeration vs an olive oil addition
Aeration vs. no/little aeration, for sure… the olive oil thing may come later 🙂
Aeration vs no aeration vs olive oil.
Love the experiments. On the effects of mash temp proposed experiment, I’d think that the extreme example of 145 vs 165 would be much more useful if it was done at something like 150 vs 156. Those temps are often touted in recipes as producing different sugars and thus different final beer. While 145 vs 165 would potentially show a difference, the results of 20 degrees difference would be of little use to me in my regular brewing. Knowing that 150 and 156 produced the same, or different, results would definitely help me on my next brew day.
Agreed, the plan is to compare less extreme temps. Cheers!
Can you do one on the decoction method? Is it necessary and does it improve on flavor and/or efficiency?
Yes. We will do it 🙂