Re-Using Yeast

Yes you can, but there are consequences for doing so. Just realize you are pitching too much yeast which can lead to less ester formation. Also, fermentation kicks off fast and furious - expect the krausen to blowoff and temperature to rise quickly. And according to my side by side tests of repitching a barleywine onto an IPA yeast cake vs. pitching new yeast, the reptiched seemed more muddled in flavor than the new yeast batches.

 

Can you provide the specs or recipe on the ale you brewed and how long ago? That will help people diagnose how healthy your yeast would be.

 

I pitch on cakes quite a bit. I have not done a side by side but have had no faults by doing so. Good luck.

 

Brewing "another one in the same style" using this technique offers the opportunity for an interesting experiment: it would be great if you could do this and offer your observations about whatever differences you notice in the fermentation character of the beer.

I think it's probably more common to brew a different, "bigger" beer for pitching onto a yeast cake. I have done this with lagers, brewing a 1.048 pilsner and then using the yeast cake to ferment a 1.092 doppelbock. In this way, you can minimize whatever potential problems might exist with overpitching, which I tend to believe would likely be minimal, anyway, but some people take very seriously.

 

I do it, though not a lot, as washing gives a cleaner yeast. I have brewed pale ales, in fact, with the idea of pitching a high grav IIPA on to the cake, to save on the cost and time of yeast starters. Keep in mind if you go from hoppy to non hoppy it may give less than optimal results.

 

I do it often but with a plan. For the most part, the second brew is higher gravity, the same or darker SRM, and hoppier (generally, the second beer is not going to be a simple/delicate beer). You can also toss out some of the yeast cake in an attempt to reduce the pitch rate/trub/dead yeast. Nowadays, I'll catch/wash half of the cake and store it away, then rack on the left over cake. Or I'll do a double brew day and split the yeast cake into 2.

It's not best practice but if you plan it right and only rack on the cake 1 time, then I don't think anyone would notice anything off. I wash the yeast after it's gone through 2 worts.

 

What makes you expect this? Usually the homebrew store gives you what you ask for. Not always, but I would point a finger in a few other places before here.

In no particular order:
Batch size needs to be calculated Pre boil and Post boil
Gravity for post boil should have been measured and checked
Grains and DME/LEM should have been measured and checked for potential gravity
Sparge volume should be measured and checked

 

Here's the beer I think he's referring to...
http://beeradvocate.com/community/threads/super-low-og.129121/
Hard to tell what happened, because he didn't answer anyone's questions.

 

I agree with those who've said that it seems unlikely the shop would botch your order that badly. If you're used to handling grains, the difference between base malt and specialty malts is pretty obvious. I doubt if somebody would have substituted 8 lbs of C60 or something like that for your two row, but I suppose stranger things have happened.

Have you been AG brewing for a while? If you want to share your method, your usual efficiency, all that stuff, we might be able to troubleshoot. Otherwise I'd be hesitant to just try the same recipe and expect double the OG.

And remember: there's always extract.