[Kaiser]

I visited multiple Czech breweries.
They use open tubs (like Anchor Steam) to do primary ferment.
I do not think that they remove the krausen. 

they may not remove the Kräusen but they also tranfer the beer to the lagering tanks before it is completely done fermenting and the Kräusen falls.

At the AB brewery that I visited the gunk sticks to the top of the fermenter.

Kai

[Thirsty_Monk]

I visited multiple Czech breweries.
They use open tubs (like Anchor Steam) to do primary ferment.
I do not think that they remove the krausen. 

they may not remove the Kräusen but they also tranfer the beer to the lagering tanks before it is completely done fermenting and the Kräusen falls.

At the AB brewery that I visited the gunk sticks to the top of the fermenter.

Kai

They transfer to the cellar when they are 75% done with fermentation.
I did not see this but would not almost all the krausen be down?

I see another reason to start fermenting in SS sink

[beerocd]

6.5 gallon carboys could become an endangered species! 

5 gallon batches may become a thing of the past.

[dhacker]

 

[blatz]

I was thinking about this thread at about 7am this morning when I was doing the second blowoff jar exchange this week from my Old Ale (that ironically was overfilled *yes*, no conical this time  )

If you purposefully overfill a carboy to induce blowoff, won't the yeast loss potentially be detrimental?  Judging by the slurry I have dumped out of the blowoff jars on this old ale, I've lost at least a cup to 1.5 cups of medium density slurry. 

That's why I wonder if a bucket or conical where you can just skim the braun hefe off is a better vehicle for this practice? 

[ndcube]

I wonder if you had a piece of plastic with holes drilled in it suspended above the beer if it would provide more surface area for the bittering substance to cling to rather than just the sidewalls.

[beerocd]

Judging by the slurry I have dumped out of the blowoff jars on this old ale, I've lost at least a cup to 1.5 cups of medium density slurry. 

Why aren't you keeping the yeast for future batches?

[blatz]

Judging by the slurry I have dumped out of the blowoff jars on this old ale, I've lost at least a cup to 1.5 cups of medium density slurry.  

Why aren't you keeping the yeast for future batches?

I would but I don't know how to do that and still be sanitary.  

FWIW - I rarely use carboys at all anymore, and when I do its for big beers where if I don't save the yeast, but I still would like to learn your process.

[Kaiser]

If you purposefully overfill a carboy to induce blowoff, won't the yeast loss potentially be detrimental?  Judging by the slurry I have dumped out of the blowoff jars on this old ale, I've lost at least a cup to 1.5 cups of medium density slurry. 

I have been wondering about this as well: How much does the yeast in the Kraeusen contribute to the attenuation of the beer later? Is there enough yeast in the beer to finish the job or does it need some of the yeast to fall back and help out.

What I have read about the brewing of Weissbier indicated that the yeast should not fall back and should be removed but this summer I made a Weissbier where I blew off the yeast and the fermentation slowed down significantly after going string and having  reached about 1.035. I’m not sure of that had anything to do with the blown off yeast.

Kai

[dhacker]

Is it just the braun hefe that has the propensity for sticking /clinging to whatever it contacts? If so, and yeast loss is a concern, why not an appropriately long, sanitized length of tubing, big enough in diameter to be "bunged" into the carboy neck, stretched vertically with some sort of airlock at the end making a braun hefe collecting chimney of sorts? The braun stuff sticks, and the desirable yeast fall back into the fermenter.

I did this a number of years ago . . Kind of a cheesy Burton Union when I was gonna have an explosion. I drilled some holes in the bucket's bottom, sanitized them, pushed the stoppers and airlocks in, and pinned them to the carboy. Worked pretty well for a panic fix! 

[dhacker]

Stumbled across this as I was doing some more perusing. Nice history on British brewery practices of old . . .

http://zythophile.wordpress.com/2008/09/24/a-tasty-drop-the-history-of-an-almost-vanished-fermentation-system/

[denny]

I have been wondering about this as well: How much does the yeast in the Kraeusen contribute to the attenuation of the beer later? Is there enough yeast in the beer to finish the job or does it need some of the yeast to fall back and help out.

Being the pragmatic type, let me answer this question with a question....have you ever had trouble getting a beer to attenuate after it has had a blowoff?  I know I haven't had any trouble that could be directly related to blowoff.

[Kaiser]

I gave the two batches, which I dedicated to this topic, a quick taste tonight. It is an Alt and still rather cloudy after 4 and 2 weeks at 4 C. But judging from samples under the microscope it seems to be chill haze. So I added gelatin to both.

But I tastes the hydrometer samples and I'm convinced that the batch where I allowed the Kraeusen to fall back in the beer has a harsher and more lingering finish than the batch where I skimmed the Kraeusen. The difference is not very prominent though.

Unfortunately the Alt did not come out as expected. Attenuation is rather poor due to the Munich malt I used. I used Franco Belges and this is likely the last time I use this malt. In addition to that I also used Hallertau Tradition since I have a lot of those and they must have lost quite a bit of alpha acid. But I don't think that this will invalidate the experiment.

I'll have a better idea once the beer is on tap.

Kai

[denny]

Kai, did you do this as a blind tasting?  I look forward to the results of that kind of test.

[dhacker]

Denny . . I know you are pragmatic!   (Maybe I an too . .)  

So, let me ask a question in response to your question . . Is it not possible to make an objective judgement of flavor without doing a blind test?