Pitching directly onto WLP005 - Pumpkin Ale Yeast

[kpr121]

Would it be okay to pitch an Amber Ale (AHS Fat Tire Clone) on top of a WLP005 Pumpkin Ale yeast cake? I did not have any pumpkin in the primary, but I’m wondering if the spice pack will add some different (maybe nice) flavors. I don’t necessarily need this to taste like Fat Tire, (I’ve never had it anyhow), but I would like a nice malty Amber Ale to sip on during these forthcoming cool months. I have been wanting to experiment (only done kits by the book so far) and thought this might be a good idea...

Any suggestions?

 

[kuphish]

Eh, if you're cool with the amber possibly picking up some of the flavors from the pumpkin spice, then go for it. Otherwise I'd get fresh yeast.

I personally don't like pitching on yeast cakes, but that's my own hang-up.

Let us know what you do and good luck!

 

[NorCalAngler]

I've read the problem with pitching on the yeast cake is that the yeast doesn't need to reproduce because there is so much there already. When the yeast reproduce in the early stages of fermentation that's when they produce most of the esters. These esters are desirable when brewing ales like brown ales because they add character to the beer.

The preferred method to to only capture a small amount of the yeast from the cake and pitch that in the new wort. mrmalty.com has a calculator that tells you how much of the yeast cake (slurry) to capture. That would minimize the amount of spice that ends up in the new brew.

 

[pericles]

+1 to NorCal Angler. Pitching on top of an old yeast cake means less yeast reproduction and results in a slower fermentation. The reproduction problem is increased by the fact that the yeast is coated in hop oils, which are antimicrobial. You'll also get spillover from the hops/spices/grains in your last beer, because of so much trub.

Last summer I brewed a Simcoe IPA five times in a row. I used fresh yeast in the first batch, and then pitched on top of the yeast cake for each subsequent batch. Each beer was great, but there were definite differences between them. The procedure that I hit on was to sterilize a stainless steel ladle, and scoop out half the yeast/trub mixture, and then pitch on the remaining half. When I hit on that technique, the flavor profile of the subsequent beers were more stable.

 

[kpr121]

Great! That is actually somewhat the answer I wanted to hear. So I could actually scoop some of the yeast out off the cake, clean out the fermentor, add the amber ale wort, then pitch the scooped out yeast slurry. This would minimize the amount of extra flavors produced from the pumpkin spices, but still allow me to reuse the yeast (ive been trying to brew cheaply lately, any bit helps).

Thanks guys, I'm going to try to brew tomorrow. Hopefully during a PSU rout of Kent St.

 

[pericles]

So I could actually scoop some of the yeast out off the cake, clean out the fermentor, add the amber ale wort, then pitch the scooped out yeast slurry.

If you're brewing/bottling at the same time, then you can bottle, scoop, and then rack onto the remaining yeast without cleaning out the fermenter. That's what I did four times in a row with no infections: the fementer is kept sanitized by the fermenting beer, so there's no need to clean it.

If you're NOT brewing/bottling on the same day, you'll need to find a way to save the yeast slurry until you're ready to use it. I guess you could let it sit in sterile water in a sterile mason jar in the fridge, and then just pitch that. But the truth is, by the time you've started removing yeast, and sterilizing water and mason jars, you might as well start rinsing the yeast and do the job properly. It's only a little more effort, and you'll avoid the carryover of flavors.

If you want to use the slurry, and not rinse the yeast, just brew and bottle on the same day.

 

[kpr121]

Thanks pericles, that's the plan. I'm going to start my brewing, then while it is on boil, simultaneously rack the pumpkin ale into keg, then scoop out the majority of the trub/yeast, leaving only a bit (i'll have to research mrmalty to see exactly how much, but i'm thinking like 2 cups or so of slurry). Then when the brewing is done, just pitch it right into the fermentor after cooling of course.

Man, I can probably justify this to the SWMBO that it is saving me at least a couple hours (as opposed to kegging on seperate days then brewing). Then I can brew more often with all that saved time. What a vicious cycle!