Combining small batches into a large fermenter

I'm building a smaller (3.5 - 4 gal) electric brewery to use indoors during the summer and am considering combining 3 batches over 3 days into my sanke keg fermenter...

So the question is, is this a good idea? Can I brew the first batch, pitch, then on day 2 add the 2nd batch and repeat on day 3? I'm thinking that this'll give the yeast plenty of time to multiply without stressing them, but thought I'd defer to the experts here...

Sure. Virtually every brewery does this. Widmer has a 250 barrel system and 750 and 1000 barrel fermenters.

Never done it, but I would be careful not to aerate the wort too much on the second and third day. Maybe aerate the wort prior to pitching and siphon into the fermenter so as not to add much more oxygen.

Sounds interesting though, nice to have an indoor setup. Good luck!

Thanks folks - it was the timing that I'm mainly concerned about. I know the big guys blend multiple batches into their fermenters, but they brew those batches back to back. I'm wondering what impact, if any, the day between batches will have...

I think you'll be fine, the only issue I see is that once the yeast start the initial multiplication stage, you don't want to introduce oxygen into the wort. So I would say after the point of boil, try to be careful to agitate the wort as little as possible.

Other than that, I think you should be alright.

Sounds like not "dumping" the additional wort would be the right way to do it. A slow siphon into the fermenter from BK after chilling.

dont you need oxygen in the wort that you put in the fermenter on the 2nd and third days?

Andysam, I don't claim to be an expert on this, but from what I understand, during the boil you actually extract gasses (oxygen being one of them) from the wort because gasses are less able to stay in liquid the higher the temp. (This is why it is more difficult to carbonate kegs at room temp than it is at 40°). The problem is, during the initial stages of fermentation, the yeast actually use oxygen to build and strengthen their cell walls while multiplying. Once this has happened and the yeast begin to convert your sugars, oxygen becomes an enemy. It can react with the yeast to create diacetyl and cause premature staling.

Because of this, I would think if you aerate your initial wort and give your yeast enough initial oxygen to create healthy cells, you won't need the addtional oxygen on your 2nd and 3rd day. You can gently add the wort (siphon) to your fermenter and the yeast will have had all the oxygen they needed to get jumpstarted, then they can get to work on the sugars.

Becasue you are doing back to back batches quickly, you may not have that much of a problem, but if it were me I wouldn't aerate past the first day.

I found this article (http://www.howtobrew.com/section1/chapter6-9-3.html) from Palmers' book how to brew that seems to support this theory. You can check it out and decide for yourself. Good luck!

Thanks for the replies folks, I've been on vacation this week (including an awesome time at Stone Brewing Co.) so I'm just getting caught up now. Once I get the new brewery up, running, and dialed in I'll try it...

Bump from the dead...

So... how did this work out, or has anyone tried this recently?