Pitch onto 5 day old yeast cake or make starter?

I'm brewing another batch of cream ale tomorrow. I've got a yeast cake from an American Wheat that I transferred to secondary on 3/28 (5 days ago, is it still good?) still sitting in a capped primary. I've also got some washed yeast from the last batch of this same cream ale that is about a month old. Both the American Wheat and cream ale use safale us-05 and have OG's of 1.040. So what would you do? Pitch onto the 5 day old wheat yeast cake or make a starter from the washed cream ale yeast?

And when people say pitch onto the yeast cake, does this mean simply dumping your chilled wort right into the fermenter with the yeast cake & trub from the previous batch without any cleaning?

Make a starter from the washed yeast. It's a better option. Is there a layer of beer on that cake? If not, than the yeast should be tossed. Either way I just don't like the idea of pitching my work from a brew day into a 'dirty' fermenter. If you MUST pitch on the cake, at least toss half of the cake so you're not overpitching. Anyway, if you make a starter with that month old yeast you'll be able to control the pitch rate and the resulting character of the beer – something that is really hard to do if you pitch on a cake.

Thanks, I got a starter going first thing this morning. My homemade stir plate isn't the prettiest, and doesn't have a speed control, so it was fun trying to use different thickness bowls and tupperware lids to achieve just the right height to keep the fan speed slow enough. It's going now though. It was just supposed to be a test stir plate to make sure I was on the right track before building it properly, but it'll have to do for today.

On the 5 (now 6) day old yeast cake, I did leave about a 1/4-1/2" beer on top of it thinking this would keep it good until I had time to wash it. Am I right or should I toss it?

I'm in the same position because my brew day cancelled for an out of town emergency. Now that I'm back I plan to brew on Wednesday and want to use a yeast cake I sealed up last Thursday night. There is about 1/2" of beer on top of that yeast cake.

Should I just get a starter going tonight from that yeast cake or can I use the cake (after removing about half of the trub)?

If you have a sufficient amount of beer covering the yeast cake, the yeast should be fine. As said before though, it's best to wash the yeast from the trub and make a starter with it than to just toss the wort in a dirty fermentor. It's much easier to control the character of the beer with a proper pitch rate.

I pitched a new batch onto a Cake that had been sitting for 3 days or so on Saturday. There wasn't much 'beer' left on the cake but I gave it a shot.

Within 30 minutes, the new batched pitched onto the cake was going NUTS. Within 3 hours it needed a blow off tube for a beer that was only 1.054.

It was the most violent and rapid fermentation I have seen so far.

I assume this activity means my cake was fine.

Would anything else, (bad) cause such a rapid and violent fermentation?

Forgot to add, does the fact that it is a top cropping yeast (american ale II 1272) make a difference?

It's not 'bad' necessarily. It just won't have the same characteristics as a proper pitch rate. Although I am not an expert on pitching on a cake, I do know that pitch rate has a dramatic effect on ester and fusel production. Fast vigorous fermentation is not always a good thing. Yeast also love really warm environments and will go nuts at 85F but it doesn't mean it is the best situation for your beers.

R2-D2 said:

Forgot to add, does the fact that it is a top cropping yeast (american ale II 1272) make a difference?

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If it's a top cropper, I would top crop the yeast after it has attenuated about half of the potential gravity points from fermentation. That yeast will give you a higher viability and will be more likely to produce consistent fermentation characteristics. Next time boil some water and add it to a small jar and seal it up to cool. Once cooled open the jar and scoop two or three spoon full's of dense yeast from the top and put the jar in the fridge. It will settle into a nice cake and give you about the same quantity of a WL vial. Then bring it out and make a starter when you're ready.

I've pitched onto week(s) old yeast cakes before without issue. I usually dump out part of the yeast when reusing a cake to avoid overpitching, but I wouldn't worry too much. It's so much easier than washing everything and making a starter and all of my beers have turned out great.

I pitched straight onto the cake with a Kolsch and my free beer drinking friends thought it turned out fine. I've never needed a blow-off tube either but I try to keep the temps low so that might help. Unless you're entering a contest I think you're fine using the cake.