Aeration/oxygenation after fermentation starts

Would it be helpful to make a starter with another package of yeast to build cell count and pitch to see if they finish? I've managed to get yeast to clear up some diacetyl this way, but am not sure that you can expect to shave 20 points of gravity, given the stress of pitching into a high alcohol env't.

My only experiences with egregiously stalled fermentations have been in two small batch mead experiments. My solution was to mix the meads with carbonated water for a less sweet, refreshing beverage. That's not the solution you want here.

 

http://www.siebelinstitute.com/prod...ypage=flypage.tpl&product_id=20&category_id=9

The only other sources I have are my notes from Siebel, which I am not allowed to share. It is completely possible that your beer right now would actually have a few things going for it that would lead to lower esters than if you had aerated to start, but if you aerated now I would bet that you would then have esters and fusels form. An easy way to think about it, is anything that makes yeast reproduce increases esters and fusels. That is why when you overptitch, the yeast contributes less esters.
So you didn't aerate, the yeast didn't reproduce as much as they would have in an ideal fermentation, and that one factor lead to decreased levels. Than you have the stress which would increase the esters potentially back to a normal level. But, the types of esters are probably different. Instead of ethyl-acetate, you could have ethyl hexanoate which is a milder flavor (for me at least) and has a licorice, red apple type flavor. I found this ester to be more difficult to pick up at a concentration of 3 times the flavor threshold in a spiked sample of Budweiser than most other flavors. I hope the beer comes out well for you!

 

Interesting discussion. I have heard of people doing a second blast of oxygen 24 hours after pitching with high gravity beers, but I have not done so. I've never heard of anyone recommending oxygen as a means of re-starting a stalled or slow fermentation, and I would be wary of that idea for the reasons stated above: it's questionable whether this would result in any additional attenuation, and it seems like a good way to oxidize the beer.

When in doubt, I tend to fall back on two common sense notions: 1) if something is not common practice, there's probably a good reason. People have been brewing beer for a long time. There's good money in it. Almost everything that you can think of to try has been tried. The things that work become common practice. The things that don't ... don't. 2) Most brewing problems are best addressed with patience. In this case, it doesn't sound like the OP necessarily has a problem at all: the beer is fermenting, albeit slowly, and will probably reach a reasonable degree attenuation for the style in due time. (If it doesn't quite get there, it'll still be drinkable. And you'll next time that you need to aerate more thoroughly at pitching.) So why do anything that could risk ruining the batch?

 

Questioning what others have suggested, would adding more yeast work? You are introducing the yeast into a pretty alcoholic environment.