Interesting

[Gymrat]

Our local brewpub (which was named best in America last year) has two half size fermenters called R2D2 and C3P0. They always split batches in those and put two different yeasts in the same beer. This time they did a dry stout. All they would say about the yeasts is that one had less attenuation. I figured that would be the one with the most malt flavor and complexity. I was completely wrong. The one with the higher attenuating yeast had far more complexity to my pallet. I may have to start rethinking my choice in yeast when I do a stout or a porter.

[John Sand]

That is interesting. While not neglecting grain, I now think that hops and yeast are the prime drivers of flavor. In other words, changing your grain bill a bit, or your mash temp, will only have a slight effect on flavor. Big changes will be wrought by changing yeast or hops.

[Foothiller]

A couple of years ago I did a comparison where I brewed one-gallon batches of the same amber ale, varying only the yeast. Each produced 6-8 12-oz bottles, just enough to taste them side-by-side in pairs with the others. For each, I used a couple of grams of the yeasts as I used the rest in different recipes. They were not brewed side-by-side, largely because the various yeasts have different optimum temperature ranges. The differences were striking, given that only the yeast varied. That taught me a lot about the yeasts' characters. The yeast, grain, and hops all make their contributions, and minerals in brewing water also makes a difference as it turns out later.

[mashani]

The profile created by various strains can make a big difference in final product. One yeast might throw dark fruits or citrus like flavors into the mix where another might seem more "mineraly" for example, and of course there is the banana and bubblegum or pepper and cloves in some yeasts. Attenuation isn't the only factor, IE if you split a batch with London ESB and West Yorkshire yeast, both will attenuate to around the same amount, but still won't taste the same at all (although both would be delicious I'm sure). In my Belgian world, Chimay yeast and Westmalle yeast would yield very different flavored products. And temperature fermented at can make a huge difference too. I can make wildly different beers with Westmalle yeast depending on what I do with temperature control (or intentional lack of it), all of which will be good, but not at all the same.

It makes me sad when I see folks who only brew with S-05 or WLP001.

[Gymrat]

That is interesting. While not neglecting grain, I now think that hops and yeast are the prime drivers of flavor. In other words, changing your grain bill a bit, or your mash temp, will only have a slight effect on flavor. Big changes will be wrought by changing yeast or hops.

I don't think hops are the prime drivers of flavor. They certainly can be if they are used in abundance as in an IPA. I still think the mash temp has a significant effect on flavor as it is a determining factor how well the beer will attenuate. I know grain bill makes a huge difference on the flavor of a malty beer. My red ale and my scottish ale both taste incredibly different. Both only had a bittering charge of hops. Everything goes into the flavor of the beer, grain bill, mash temp, yeast, hops, hop schedules, fermentation temperature. We are playing with a lot of factors when we dial a beer in to the way we like it.

[Gymrat]

The profile created by various strains can make a big difference in final product. One yeast might throw dark fruits or citrus like flavors into the mix where another might seem more "mineraly" for example, and of course there is the banana and bubblegum or pepper and cloves in some yeasts. Attenuation isn't the only factor, IE if you split a batch with London ESB and West Yorkshire yeast, both will attenuate to around the same amount, but still won't taste the same at all (although both would be delicious I'm sure). In my Belgian world, Chimay yeast and Westmalle yeast would yield very different flavored products. And temperature fermented at can make a huge difference too. I can make wildly different beers with Westmalle yeast depending on what I do with temperature control (or intentional lack of it), all of which will be good, but not at all the same.

It makes me sad when I see folks who only brew with S-05 or WLP001.

I only use dry yeast. But I use 04 for my British style ales, I like Nottingham for my IPAs because it attenuates so well and really drys them out. I have always used Windsor Ale yeast for my stouts and porters in the past because of it's poor attenuation. I always felt it would give them more body and better mouthfeel while leaving the flavors of the malts in tact. I like BRY-97 for my American style ales or anything that I want a clean flavor in. I have used Munich for hefes and bell star saison for my Belgian ales.

[mashani]

Gymrat, you might want to experiment with the new Abbaye strain for Belgians. I have a couple of packs (of the Danstar/Lallemand variety) I'm going to try out when my temps warm up. I love Bella but it's not really a replacement for Belgian yeast like Westmalle/Chimay, it is more of a replacement for Wyeast 3711 (French Saison). I will use Bella in any beer where I would have used 3711 in the past. I consider it a direct replacement. But all 3 yeasts are very different in character.

I know that George (BigPapaG) tried the Abbaye end of last year and was pleased with it. His description made it sound like it could be good as an alternative to some liquid Belgian strain (unsure which one until I try it). At the moment, there is not a good dry sub for Westmalle or Chimay strains, unless this one happens to be it.

From a "English" perspective, I can tell you that I like both Nottingham and S-04. I like Windsor in milds. Like you also like Nottingham in IPAs.

But none of them can replace London ESB or West Yorkshire liquid yeast (or Ringwood) in certain beers I might brew.

And you can't brew a proper Kolsch without using Kolsch yeast or a cold fermenting German Ale yeast, as they are almost lager/ale hybrid yeasts, they throw off sulfur compounds like a lager yeast which although it dissipates leaves a "crispness" that you can't get from Notty or S-05 even fermented cold. Side by side you would be able to tell the difference in the finished product, a "crispness" vs. a "softness".

So although I do use a lot of dry yeast, I don't limit myself to it, because I just can't get some of the results I want with it at times. It just depends on what I'm brewing.

[yankfan9]

I would even say that the boil has it's role in flavor development, depending on how aggressive you boil, the length, etc.

[D_Rabbit]

There are so many different things that lead to every bit of a beers profile. The yeast can effect it, the grains/hops and the mash temp. Even if a yeast attenuates at 75-80%, if the mash temp is set for more body, that will give the effect of a maltier backbone due to how full it tastes. Most peoples perception is that if the beer tastes thicker (more body) than it is a malty beer. There are so many different variables to work around to alter how you want the beer to taste.

I can see how the higher attenuation will lead to a more complex flavor due to all the cleaning up the yeast does prior to dropping out. It leads to a cleaner and more crisp profile which lets that grain/hop profile really shine. With that being said, if you lower your mash temp a little it will help keep the full body you are looking for with a cleaner more crisp taste from the yeast.

Anyone confused yet? I might be after typing that.

[berryman]

I have nothing really constructive to add except this is starting out as a very informative thread, a lot of good knowledge and ideas here and I'll be following it. I think the choice in yeast and fermenting temps adds more influence to a beers final outcome then the other ingredients and techniques up to a point.

[FedoraDave]

It makes me sad when I see folks who only brew with S-05 or WLP001.

This is so very true. The science of yeast development and propagation has come an awfully long way just in recent years, and there are so many strains that are developed for specific styles of beer. I'm sure any lager yeast would produce a passable California Common, but when White Labs has a San Francisco Lager Yeast, why use anything else? (Well, unless other manufacturers market a similar type of yeast specifically for that style; I'm just sold on White Labs for my South Ferry Steam Beer)

As I develop a recipe, I look at the BJCP guidelines for that style, to get an idea of what grains/hops would best fit the style. Then I start formulating my grain/hops bills on BrewToad to see if it's within the style's gravity, SRM, IBU, etc. And then I research my yeast, usually going to Northern Brewer's website or even White Labs' site to read about the characteristics of different yeasts that might work with the recipe.

I think it's made a big difference in the quality of the final product since I've been doing this.