Flocculation and bottle conditiong question

The short story here.... I started brewing extract beers in 2001-2004 and didn't know much about what I was doing. I just pitched whatever dried yeast the HBS had because it was cheap. I always had trouble with under-carbed beer.

I just started brewing again using Wyeast 3068 (German Weissbier), and learned to rinse my yeast for the next batch. So now I've been trying to learn and understand the behavior of yeast. This yeast is low flocculation, and bottle conditioning carbonation was excellent!

Is there a correlation between flocc levels and suspended yeast left after ferment to where it affects carbonation? For example if a high flocculation yeast was used, less suspended yeast for bottling making an under carbed beer?

Next question is on cold-crashing effect on yeast and then bottling. I have been fermenting my Weissbier at 65 degrees. About 2-3 days after it stops bubbling and the yeast flocculates, I move it out to my garage and cold condition at 50-55 degrees for 7-10 days. Then I move it back into the house 65-68 degrees for a couple days before bottling. Did this defeat the purpose of cold crashing? Or is it better to rack / bottle cold when it is 50 degrees? Will there be enough yeast if bottled cold to make sufficient carbonation?

Thanks for the help!

Flocculation is a yeast's tendency to form clumps. High floc yeast do tend to settle out faster as gravity has more effect on the larger groups of yeast stuck together. "Cold crashing" is cooling a beer down to accelerate the settling process. Unless you are brewing a style you want really clear with a low floc yeast, cold crashing is really not necessary. In fact, in the case of a weissbier you may be hurting it's character a bit since this is a yeast driven style. I personally have never cared much about clarity and never cold crash for that purpose; I might chill in the carboy if I feel a beer is ready but I can't get to it for a few weeks (or months). For purposes of bottling you should have enough residual yeast either way, but you certainly are bottling with fewer yeast if cold crash and use high floc strains. I'm not sure at what point it would become a problem for bottle conditioning, but I suspect it's way longer than most homebrewers are willing to wait. We tend to be an impatient lot!!!

Even if your beer looks clear, there are still plenty of yeast for carbonation. Even if you cold crash.

Is there a correlation between flocc levels and suspended yeast left after ferment to where it affects carbonation? For example if a high flocculation yeast was used, less suspended yeast for bottling making an under carbed beer?

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Not really, there is still quite a bit of yeast left in suspension for carbonation. One thing to note though about high floc yeast is the tendency of the yeast to drop before fermentation is complete. This can be avoided by ensuring proper fermentation temperatures.

About 2-3 days after it stops bubbling and the yeast flocculates, I move it out to my garage and cold condition at 50-55 degrees for 7-10 days.

Click to expand...

Bubbling airlocks is not a sign of fermentation, only gas escaping and IMO 2-3 days is not a long enough time to wait as the beer may still be fermenting out those last few points. By dropping the temp you may be forcing the yeast out before they were done. You should really verify FG before doing this

Then I move it back into the house 65-68 degrees for a couple days before bottling.

Click to expand...

If the beer was not done fermenting then the warm up may re-start fermentation as the yeast warm up, hence the reason to verify FG first.

Really what should be done is all the beer to ferment completely and then provide an additional week for the yeast to clean up and clear the beer. Then cold crash for 2-3 days, then bottle. There are still enough yest in suspension to handle the carbonation process unless you space out and leave the cold crash for weeks......

Is there a correlation between flocc levels and suspended yeast left after ferment to where it affects carbonation? For example if a high flocculation yeast was used, less suspended yeast for bottling making an under carbed beer?

Click to expand...

Not really, there is still quite a bit of yeast left in suspension for carbonation. One thing to note though about high floc yeast is the tendency of the yeast to drop before fermentation is complete. This can be avoided by ensuring proper fermentation temperatures.

About 2-3 days after it stops bubbling and the yeast flocculates, I move it out to my garage and cold condition at 50-55 degrees for 7-10 days.

Click to expand...

Bubbling airlocks is not a sign of fermentation, only gas escaping and IMO 2-3 days is not a long enough time to wait as the beer may still be fermenting out those last few points. By dropping the temp you may be forcing the yeast out before they were done. You should really verify FG before doing this

Then I move it back into the house 65-68 degrees for a couple days before bottling.

Click to expand...

If the beer was not done fermenting then the warm up may re-start fermentation as the yeast warm up, hence the reason to verify FG first.

Really what should be done is all the beer to ferment completely and then provide an additional week for the yeast to clean up and clear the beer. Then cold crash for 2-3 days, then bottle. There are still enough yest in suspension to handle the carbonation process unless you space out and leave the cold crash for weeks......

EDIT: Delete, double post, sorry , not sure what happened!

Thanks for "clearing this up"

I moved to 50 degrees after a couple days of no visible activity. (Weihenstephan yeast is VERY active). And, confirmed FG (1015) with a FFT. (OG 1065, FG 1015). My first batch had OG 1050, I think I improved my mash technique. lol

I found this procedure from "breukaiser" to lower the temp of Weissbeir after 3-5 day primary. However he makes no comment or follow-up on the cold conditioning process that left me confused.

ScrewedBrew said:

... And, confirmed FG (1015) with a FFT. (OG 1065, FG 1015) ...

Click to expand...

How exactly do you confirm your FG with a Fast Fourier Transform (FFT)? I want to do that!