When I first started brewing I made overly complex grain bills and hopping schedules. I would find myself regularly perusing forums for tips on how to make the perfect grain bill and which hops would go best with that. Though this may be something that was unique to me, I am guessing that quite a few home brewers start out this way. The thinking is probably “well great beer has so many favors so a complex malt and hop bill must drive this.” To beginning Brewers the concept of beer flavor being significantly driven from yeast doesn’t quite register. I learned this when I was lucky enough to take a trip to the Czech Republic and Germany with my wife’s family. Up until this trip I would regularly deride German beers with friends as being behind the times and having nothing to them, no complexity, they all tasted the same. When in Europe I tasted Pilseners and Helles with more complex flavor than a great IPA. Hefeweizens suddenly tasted as complex as an imperial stout. Certainly some of this can be chalked up to the surrounding and experience I was having on the trip. However, since that trip something has always stuck with me: complexity of ingredients does not make a complex beer. Since this trip I’ve sought to simplify my recipes and focus more and more on my process (hence the name of this blog), and to me yeast is much more of a part of the process of brewing than the fourth ingredient in beer, yeast are your billions of cells of brewing friends that help you make a beer, just like someone helps you lift a HLT to mash in.
While many parts of the process of brewing create the end result, yeast may be the most significant factor. Throw a lager yeast in an imperial stout wort and ferment at 65 degrees, might not come out tasting like you hoped. Likewise pitch .25 million cells/liter of cal ale yeast and ferment an IPA at 60 degrees, you’ll make beer, but it may not taste as you envisioned. Many people have done amazing work researching yeast, and while I’ve certainly been a beneficiary of their time, I don’t intend to replicate their results here. The purpose of this experiment is to look at just how much yeast plays into the resulting beer on a home brew level.
Note: if you’re lucky enough to live close to white labs you can actually taste the results of an experiment like this with many more yeast strains!
Given my inspiration for this experiment really came from the Hefes I tasted in Germany I thought it would be fitting to have half of this experiment be a Hefe. Additionally, a simple grain bill should make any differences apparent. Lastly, I’ve been meaning to try WLP300 for a while. I’ve brewed a lot of wheat beer and my preferred choice of yeast was always WLP351, since this is rarely available to me, I often had to use the Wyeast “equivalent.” (That will be an experiment for this spring). Regardless I’ve never brewed with WLP300 so I’m very excited to try! For the second strain I will use my staple yeast WLP029. I’ve been using kolsch yeast for quite a while in all types of styles with great results. My third beer ever was an attempt to clone New Glarus Spotted Cow, while that try wasn’t really successful it wasn’t a total failure since it lead me to the kolsch strain. I prefer the white labs strain to its wyeast “equivalent” (they are certainly not) due to the fact that wyeast’s strain isn’t very flocculant and lends a harsh yeast character to the finished beer.
To examine the differences of one wort fermented with two separate yeast strains in the same conditions.
Brew 10 gallons of wheat beer base wort and ferment with two different yeast strains under the same conditions.
Recipe: Bavaria vs Köln
For 10 US gallons
O.G. – 1.050
F.G. – 1.014 (calculated)
IBU – 22
SRM – 5
ABV – 5.0%
11# – Avangard Pilsner
8# – Avangard Red Wheat Malt
0.5# – Weyermann CaraMunich II
1.4 oz Northern Brewer – FWH (6% AA)
1.0 oz Northern Brewer – 30 min
0.5 oz Northern Brewer – 5 min
0.25 oz Hallertau Mittelfruh – 5 min
WLP300 Hefeweizen Ale – Five gallons
WLP029 German Ale – Five gallons
Bru’n Water yellow and malty
Mash at 152 for 60 minutes
60 minute boil
The night before brewing I bought my ingredients and woke up early the next morning to start brewing. I added minerals, heated water, and mashed in. Thanks to great software developed by people much smarter than me I hit target temps and PH!
After the boil I cooled the wort to my pitching temp using chilly Denver ground water, oxygenated the worts for 60 seconds, and pitched the two pre-made starters saving some WLP029 for another brew day. I used the hybrid calculation for both starters to ensure consistency (sorry under pitch Hefe enthusiasts!). Both beers were fermented using my trusty Denver winter ambient method described in the Midwestern ale yeast experiment.
12 hours post pitch
24 hours post pitch
Around this time my wife and I decided to drive to Wisconsin to visit some family for the holidays. A great time was had and much New Glarus was consumed!
When I returned ten days later, the beers were sitting at final gravity.
Both beers finished lower than my software had predicted. I wasn’t sure what to chalk this up to and it made me semi concerned. However, I did take solace in the fact that both were lower and neither tasted of a bacterial infection. At this point it’s quite obvious these beers were very different. The Kolsch tasted like Kolsch should, albeit a young Kolsch. And the hefe tasted as I had hoped it would. The difference in clarity to me was shocking. I generally use a mini theif to pull samples so the samples are usually clear. The hefe looked like nothing had dropped. Just based on this sample I would never guess these beers are exactly the same other than yeast.
Normally I would fine these beers with gelatin and keg. Since I really enjoy my German Hefes to be cloudy, I skipped that step for that beer and only fined the Kolsch (and come on, a clear Hefe! I guess Kristalweizen is a thing so I’ll shut up). Each beer was kegged and set to serve.
You may be thinking to yourself “you idiot, obviously these beers were going to be very different from the start.” While of course this is true, the real purpose of this experiment was for me to examine beers of Germany and look at two styles which have a very similar grain bill and how they can be so different depending on the smallest input, yeast. This experiment was also a great way for me to prep some participants into the mindset of looking for differences in beer. When this beer was served to participants they were asked:
1. Are these beers different?
2. What makes them different?
3. In your opinion, could these beer be the same beer?
4. What flavor does this beer exhibit?
5. Which beer do you prefer?
Answers to these questions of course were what you would expect for 1, 2, & 4 but the interesting thing is most people did not answer yes to number 3. I think that this is a pretty profound result, while this is just one small experiment that didn’t really have a significant amount of participants no one thought these were the same beers. The recipe was not complex, two basic ingredients and a touch of on caramel malt, yet the yeast produced two complex beers that no one thought were the same. What I take away most from this experiment is further proof that a complex recipe does not in and of itself make a complex beer. Choice of yeast may in fact make the most significant impact on our end product and how that tastes. As home brewers we often fall into the trap of reading descriptions of malts and envisioning them in our beer. It all sounds so sexy on paper: “a little bit of chocolate flavor, some toasty biscuit, a touch of honey, oh and don’t forget that hint of coffee, oh and last a little toffee to go on top.” The end result of those complex recipes however may not meet our expectations and can at times feel muddled. Certainly going forward I will be paying much more attention to my recipes and simplifying grain bills where I think I can accentuate a few flavors and really let the yeast do their things!
My thoughts: Both beers were nice easy drinking pleasant beers. Having ten gallons of refreshing beer is perfect for this time of the year with football and gatherings. One thing I did take away from this is not to use Northern Brewer in these two beer styles (I had it lying around from Cal Common experiments). It was fine in the Kolsch, however the woody/minty flavor didn’t meld very well with the Hefe. As to my thoughts on WLP300, I want to try it again compared to 351 pitching normal ale cell counts. It’s a great Hefeweizen, but something isn’t 100% right.
Cheers and as always feel free to email me thoughts, comments, or potential future experiments.