Stirring ferment batch? Harmful or helpful?

[glockspeed31]

Just had an idea and wondered what results would occur.

Brewed a batch of Summer Ale and has been in the fermentor for 7 days now and the hydrometer says it's ready for bottling, but I'm not. What would happen if I gave the batch a good stir and then let it sit for another week? Would the yeast kick up again and really clean up everything? Would the yeast be viable after another week to be able to convert the sugars when it gets bottled?

Thanks

 

[Special Hops]

Do not stir. That will pull in oxygen. Just let it sit. It will be fine. Plus more stuff will fall out and you will have clearer beer.

 

[aquenne]

this begs the question. what if the vessel was under the pressure of CO2 (no oxygen could make its way in).

Does rousing the yeast help or hurt? This would be before the beer has hit its FG and the yeast is still working...

 

[brockettbrews]

dont stir it!!!!

 

[JonM]

There's plenty of yeast in suspension. No stirring needed. Just let it sit. Cheers!

 

[aquenne]

Sorry, i didnt mean physically stirring (with a spoon), i meant more of a gentle rocking of the fermenter.

 

[Yooper]

Sorry, i didnt mean physically stirring (with a spoon), i meant more of a gentle rocking of the fermenter.

Don't do that either. The whole point of letting it sit after fermentation ends it to clear up the beer a bit. Why would you agitate it, only to let it sit and clear again? That doesn't seem to make any sense to me.

 

[bob1006]

Don't shake or stir, it will do the cleaning on its own. Give it another couple of Weeks and bottle it.

 

[amandabab]

If the ferment isn't stuck, and the hydrometer says its done, what are you trying to accomplish?

The early activity stirred it.
You will never even approach a recirculating fermentation on homebrew scale.
If its ready to bottle and you aren't just wait. IF you can't leave it alone and just have to do SOMETHING, rack it to a secondary.

 

[aquenne]

sorry not trying to spark any wars

I did say this was before the beer hit its FG. Nothing to do with clearing the beer. Seems this is a touchy subject.

I only meant this as a way to HELP the yeast. We use stirplates to keep all yeast in a fermentation with a starter, im just thinking about it on a (relatively) larger scale.

 

[aquenne]

Seems it may be a helpful technique in slow to end fermentations

Some fermentations begin to slow down toward the end because of premature flocculation of the fermenting yeast. A simple technique to keep these sorts of fermentations on track is to "rouse" the fermentation. In a commercial brewery, rousing may involve transferring the beer to another fermenter or pumping the beer around in the fermenter to mix it up, but at home rousing is simple - just gently rock your carboy or fermenting bucket and the fermentation has been roused!

http://***********/stories/wizard/a...elines-on-using-yeast-in-high-gravity-brewing

 

[dbhokie]

I think its a fair enough question. Many famous breweries ferment openly. Stir the yeast, depending on and don't have filtered air, or positive pressure with careful containment. There aren't fruit flies flying around everywhere, and it is hard for me to imagine, but there is something romantic about such processes, a touch of the arcane. From my understanding and remembering of a couple brewery tours, the fermentation byproduct of CO2 keeps oxidation at bay, and they rouse the yeast in some of these breweries many times with long handled stirrers. Sierra Nevada, many English brewers and famous Bavarian and Belgian brewers ferment openly in non-filtered air environments, and stir yeast in their batches during fermentation. A lot of beers are made this way that aren't lambics and such as well. It isn't entirely just to introduce bacteria, it has been done this way for thousands of years, as well as closed. of course it would be great to have a stone yorkshire square of course too, or something of the like. It does often raise to question in my mind why so many are so hesitant.

I plan on doing an open Abbey soon. I'm interested in the ester and taste profile differences there will be between it and the one I finished a couple months ago closed.