What is a Kolsch Style

Wow. This has got to be one of the biggest collections of misinformation I’ve seen in a while regarding Kolsch.

Let me start by stating the following:

Saccharomyces cerevisiae = ale yeast, which is top fermenting.
Saccharomyces pastorianus (aka s. carlbergensis) = lager yeast, which is bottom fermenting.

These are two separate subspecies of yeast and are discrete biological designations. Ale yeasts can ferment cold, but usually perform best warm, about 65-70 deg F on average. On the same note, lager yeasts can ferment warm, but usually perform best at 50-55 deg F on average.

The term lager can be taken to mean the beer was fermented with a lager yeast strain, but in the more general sense, it means the beer went through an extended period of cold conditioning before being served. This period can be from several weeks to several months and varies depending on the style and the brewers preferences.

Kolsch, like altbier is traditionally fermented with an ale strain (s. cerevisiae), but often at lower temps for an ale (60-62 deg F). This reduces the production of esters by the yeast, which is why kolsch usually has just a subtle fruitiness. The long period of cold conditioning post fermentation (lagering) gives the yeast time to settle out and reabsorb may by products of fermentation, leading to a clean flavor profile.

I have been a brewer for over 10 years and kolsch is a style I am very familiar with. The kolsch ale yeasts that are available to most brewers in the US from both White Labs and Wyeast are ALE yeasts. And all the professional kolsch brewers I’ve spoken to from Cologne refer to their house yeast strains as ale strains.

In the colloquial sense, kolsch (and altbier and steam beer) are often referred to as "hybrid" beers because they are fermented outside the typical temperature range for the yeasts used.

There were so many off-base ignorant post in this thread that the world’s supply of kolsch would run out in the time it’d take to address them all. Have any of you bothered to read the BJCP, AHA, GABF, or WBC guidelines for kolsch? Have any of you read "Principles of Brewing Science" by George Fix, Ph.D? Many of the issues that have been brought up in this thread aren’t really debatable - they’re clearly defined scientific/biological terms. If you think otherwise, you might as well start calling it the "theory of gravity."

edit:

I meant to denote lager yeast as saccharomyces carlbergensis, without the pastorianus reference.

Originally posted by rpattinson

Originally posted by puzzl
err, apparently its an Ale? Wow, never knew that or would’ve thought it.

Kolsch is a lager. A top-fermented lager. It has a primary top-fermentation and then is lagered at a low temperature.

Originally posted by puzzl

Originally posted by SilkTork

Originally posted by puzzl

Originally posted by puzzl
Why do people care so deeply about this? Can’t we just call it a hybrid style and all get along?

Not to downplay the importance of proper classification at all. I’m as much for guidelines and proper terminology as the next guy. However, this seems like a rather clear cut example of a hybrid to me, I just don’t see the point of the endless arguing that it has to be one or the other.

I agree. However, much is gained by asking questions - people involved discover more. That is how we evolve. Not asking questions gives a more quiet life, but little progress is made.

Certainly that is true, and I read a good 5 pages of this thread and learned a lot. However, the thread has basically deteriorated into a pissing contest (no offense intended), with one guy asking obscure chemistry questions he learned in college, one guy referencing books from the early 1900s, one guy referencing unverifiable conversations he’s had with brewers, etc etc. It’s clear no one is going to "win" here, because its clear people have drawn a different line between ale and lager.

Originally posted by Saco_De_Toro
Wow. This has got to be one of the biggest collections of misinformation I’ve seen in a while regarding Kolsch.

Let me start by stating the following:

Saccharomyces cerevisiae = ale yeast, which is top fermenting.

Just wanted to say I’ve enjoyed this thread immensely. Please keep arguing!

(Just do it respectfully and in the pub spirit of talking over beer. Use little smiley faces if necessary. But please don’t question the credibility of others. Everyone who posts here knows more about beer than most drinkers, and what we’re really arguing about here is semantics and philosophy. Which are much more important than most people give them credit for.)

My two cents:

One cent: For some reason, Kölsch is more interesting to me if it’s an ale. Germany has enough lagers. Let them have an ale or two, will you?

Two cent: IMO, real Kölsch in Köln doesn’t taste THAT much like lager. It can have subtle fruity notes that differentiate it and make me think a bit of ALE.

That’s coming from a drinker, not a brewer. What is this "yeast" you speak of, anyway? Sounds like hocus pocus to me.

Originally posted by JoeinUccle
What is this "yeast" you speak of, anyway? Sounds like hocus pocus to me.

Originally posted by SilkTork

Originally posted by Saco_De_Toro
Wow. This has got to be one of the biggest collections of misinformation I’ve seen in a while regarding Kolsch.

Let me start by stating the following:

Saccharomyces cerevisiae = ale yeast, which is top fermenting.

And this is where I came in.

I said that Saccharomyces cerevisiae can and does also bottom ferment. Which throws into question the notion that one can have such absolutes as "Saccharomyces cerevisiae = ale yeast, which is top fermenting."

That’s why these discussions are interesting.

If ales can be made by bottom-fermenting yeast then we need to be looking again at how we define both ale and ale-yeast.

My feeling is that the temperature is a deciding factor. Where the yeast flocculates doesn’t appear to have much of an influence on the finished taste of the beer. But the temperature does as it appears to have an impact on the activity of the yeast.

Originally posted by Saco_De_Toro
An important factor to note is how the yeast flocculate. In general, less flocculent yeasts have a greater ability to reabsorb biproducts of fermentation as they’re in suspension longer. Many lager yeasts, as with most kolsch yeasts are not particularly flocculent.

Originally posted by SilkTork

Originally posted by Saco_De_Toro
An important factor to note is how the yeast flocculate. In general, less flocculent yeasts have a greater ability to reabsorb biproducts of fermentation as they’re in suspension longer. Many lager yeasts, as with most kolsch yeasts are not particularly flocculent.

I’m with you on this. Faster acting yeasts do leave more in a beer, giving a fuller taste and body.

My understanding is that the slower acting yeasts work for longer and attenuate more, giving a cleaner, dryer, leaner taste.

The discussion here has been toward that understanding of the nature of the yeast and how it produces the finished result. Where the yeast ferments, flocculates, settles, etc, is not so important as the yeasts actual activity, which tends to be more related - from my understanding - with the temperature.

Talking about Kolsch as an "ale" because the yeast ferment/flocculate/settle at the top isn’t that helpful to an understanding of the nature of the finished product and what we are to term it.

Talking about what effect the yeast has on the beer is much more interesting.