Properly aerating a high gravity brew?

This is my first time posting on this site, but not the first brew I have done. I have been on an IPA craze lately - especially double IPA's so that's all I have been brewing.

My current brew is about four days into fermentation and has been generating for the last 3 days about 300 bubbles a minute into the water pot from my blow off tube, I would say compared to my last two double IPA's of similar gravity there is definately a more agressive fermentation - based on the amount of bubbles. I would say we are down to about a 100-150 bubbles as of this morning...

My question is if used 6 lbs of light DME and 2 cans (6 lbs) of LME and an English yeast, should I try and re-aerate while still in the primary bucket in the next day or so? For starters I definately aerated the hell out of this batch- spent a good 20-30 mins whipping the wort up with my spoon to produce a nice head on the wort - but since it is a high gravity (around 10%) I don't know if you guys recommend additional aeration while in primary? My buddy did a triple belgium of similar gravity and he said about four days in he attempted to re-aerate to give the yeast more oxygen...

I currently have not taken starting on ending gravity's on my brews out of pure laziness - so I know I won't be able to check the hydrometer readings to see how far along it is in fermentation...but in general I was just curious what you guys recommend for different techniques on higher gravity beers


I appreciate the input guys and I look forward to posting on here in the future

I would leave it alone at this point as you run the risk of causing oxidation and off flavours. I have seen strategies of oxygenating high gravity beers for the first 12-24 hours when you are trying to maximize yeast reproduction and fermentation has not fully kicked off.

Good point, I figured I'd ask since all I have been brewing is high gravity - I would assume it's properly fermenting, like I said the bubbles were pretty agressive compared to past brews...What about going into the carboy? Are there any techniques before I siphon the beer into the carboy - or do I still just go with the flow?

First, do not aerate now that primary fermentation is underway/mostly completed. It will probably lead to off-flavours in the beer (particularly since it is likely you will want to age/store it for a long period of time).

Second, you really do need to rely on your hydrometer readings to get any meaningful information about your fermentation. Rates/amounts of bubbling from the airlock provide only the coarsest level of information about degree of fermentation.

Given that it is an extract batch, you can estimate the OG relatively precisely. So it is not too late to obtain your current SG now. I suggest doing it. If it reveals that your fermentation is not complete (i.e., poor attenuation), you have two options:

1. Attempt to rouse the yeast from the bottom of the fermenter by gently stirring or shaking the carboy (probably will do little for a high gravity beer), or

2. Pitch some more healthy yeast.

I suggest trying option 1 first (nothing to lose, really, if you are very careful about not aerating the beer). If that doesn't work, you will have to pitch some more yeast to get the gravity down.

Occasionally you hear people suggest adding champagne yeast or beano or something else to get fermentation going again, but you also hear of a lot of problems developing from this. So exercise some caution before you choose these sorts of solutions over fresh yeast.

Best of luck!

freshbrew07 said:

Good point, I figured I'd ask since all I have been brewing is high gravity - I would assume it's properly fermenting, like I said the bubbles were pretty agressive compared to past brews...What about going into the carboy? Are there any techniques before I siphon the beer into the carboy - or do I still just go with the flow?

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I wait till the gravity is the same for a few days in a row then transfer to the secondary so I am not interrupting an active fermentation.

Oh freshbrew, one thing to add to my post above that I forgot to include:

Welcome to the site!

Thanks for the advice guys! I might get boo'd for the next addition of fact to this recipe BUT...

I actually added about 3/4 of a gallon past the 5 gallon mark because I was getting too many "5 gallon" batches that really only netted around 4 gallons - so I figured - screw it add a little more water before pitching the yeast and then I will net around the 5 gallons when all is said and done...I am assuming this will just lower the final gravity a little bit - is that all that you would worry about with this technique...for future reference?

I am actually just kegging the beers I have done so far, but I really think this batch will be a good one to partially bottle - which is my next question - I have one of the force carb caps that you can put on two liter bottles and I was wondering if anyone knows if it's a good idea to force carb say a liter and half of uncarbonated beer in a two liter bottle (and bottle the remaining beer)? The obvious reason would be to sample the fruits of my labor without waiting 3-4 weeks initially...so I wasn't sure if anyone has looked into this before?

Sorry if these are obvious posts - the only other forum I use is a Mustang forum - so I will have to get my bearings on what to ask and what to dig through as far as proper questions on here -

Thanks again for all the help guys!

freshbrew07 said:

Thanks for the advice guys! I might get boo'd for the next addition of fact to this recipe BUT...

I actually added about 3/4 of a gallon past the 5 gallon mark because I was getting too many "5 gallon" batches that really only netted around 4 gallons - so I figured - screw it add a little more water before pitching the yeast and then I will net around the 5 gallons when all is said and done...I am assuming this will just lower the final gravity a little bit - is that all that you would worry about with this technique...for future reference?

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You just lowered the original gravity of the beer a little bit. Which will likely result in a couple 10ths of a percent less ABV and perhaps a slightly lower body and bitterness. Nothing wrong with this, just if you plan on doing it in the future you might consider planning your recipe with the larger volume from the start. This will ensure you know what you are getting.
I am still pretty new to brewing and have been trying to get my AG techniques down, but I often end up with 5.5 to 6 gal in the primary. One of these days I will get my system dialed in.

Craig