Yeast Cakes

Mmmmm sounds delicious. But seriously, I finally got my pitching rates to a respectable level with my last 2 batches, and had a pale ale and an IPA that both fermented through the roof. Finally made a starter, for the pale, and then just dumped the IPA right on top of the yeast cake.

So my question is: I don't want to make a starter for this next batch, which will be the same pale as the first batch. It's also going to be a 10 gallon batch. So my thought was, can I just pull my 10 gallons, aerate the whole thing in two different buckets, pour about 2-3 gallons into the bucket with the yeast cake in it, swirl it up real good, and then split that beer/yeast cake slurry into 2 other buckets, and finally top them up with the rest of my wort? Good idea? Terrible Idea? Am I going to be close with pitching rates splitting the cake like this?

And I know I should start washing and doing it right, but I'll get there soon enough.

I'd check out the yeast washing thread and do it like that. If you did a pale ale then an IPA, there's going to be a lot of trub and hop resins mixed in with the cake, which can cause yeast to rapidly go south in a few generations and cause a bad ferment. Then you'll have healthy, ready-to-pitch sized containers ready to go instead of guesstimating and hoping it works out. What if you pour all the bad yeast into one of the beers and it's ruined? Why bother worrying if an extra 20 minutes of work can potentially save a batch?

Not only that, but you don't want to overpitch either, and after going through two beers you'll probably have more cells than you need.

If you're pitching a beer on top of a yeast cake, no need to aerate. In fact, I would recommend against it.

Okay, fine, I'll do it the right way. Lately I've really been trying to be a lot more careful and consistent with it, so it makes sense that I should put the effort in with this too.

I recently started to get the feeling that I've passed some of the guys at my LHBS, at least from a theoretical standpoint, from lurking these forums. It's making it more difficult to figure out how to get the practical side figured out when they don't know what I'm talking about or why I'm trying to do what I want to do.

From what I understand, with our atmosphere here in Denver, you don't get much out of aeration anyway. But what you say about not aerating on top of yeast cakes makes sense, with not really needing much of the aerobic multiplication phase.

I appreciate the advice. We'll see where I can go from here. Last final next wednesday and then I'm going to get really serious about the beer.

You need to take that cake, and pitch about 1/5th into each 5 gallon batch, and aerate the heck out of it.

If you overpitch (such as pitching straight onto a cake), you eliminate or minimize the reproduction phase. A lot of the yeast esters and character is created during this phase, which of course you will lose. And if you plan on re-using the yeast again, you will want freshly reproduced yeast, and not old yeast that has been stressed out thru a couple of brews.

I would not worry about washing it of you are going to re-pitch straight away, but I would recommend only pitching a part of the cake.

Calder said:

You need to take that cake, and pitch about 1/5th into each 5 gallon batch, and aerate the heck out of it.

If you overpitch (such as pitching straight onto a cake), you eliminate or minimize the reproduction phase. A lot of the yeast esters and character is created during this phase, which of course you will lose. And if you plan on re-using the yeast again, you will want freshly reproduced yeast, and not old yeast that has been stressed out thru a couple of brews.

I would not worry about washing it of you are going to re-pitch straight away, but I would recommend only pitching a part of the cake.

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+1 to that, and I would say washing yeast is pretty damn easy. After I rack a batch I usually throw some boiled water in the fermenter, agitate and pour into a gallon jug. Stick an airlock on it and let it sit in my mudroom for a day or so. It's pretty cold out there and my yeast drops fast. Then I pour off the water, repeat and pour into pint mason jars. It takes about 5 minutes a day, I do it when I come home from work in the mornings.

Yeah, washing yeast is the next step, and I've known that for a long time, I just haven't had the chance to get all the stuff put together. I guess I'll make that the priority over getting the next batch going.

It's good to have other people look at this stuff, there are just some angles (especially on the microbiology side) that I miss. So thanks guys.