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Pitching RIS on Pacman yeastcake?

I’m fermenting a 1.066 ale on Wyeast pacman (3rd generation). I plan to brew a 1.12 RIS in a couple weeks. I expect there to be 3 weeks from one fermentation to the next…will I be ok with the yeastcake or should i pull it and make a starter? I know 1.066 is a bit of a bigger beer to use the yeastcake, but that pacman yeast is a solid yeast and I think it can take it.

What do you think?

There really probably isn’t a need to make a starter with yeast that just came out of primary 3 weeks prior.
Now with that said…I’m not sure if that will affect how much yeast you should on the RIS. Do you plan on pitching the entire cake, or just separating the cake and splitting up again?

well, I was planning on pitching it right into the fermenter with the cake in tact. I’ve never done it before, but have read of others doing it Normally I rinse my yeast store it and make a new starter with it. I’ve not had much faith in trying to measure how much slurry I reuse as I’m sure the volume is very dependent on how much beer or water is mixed with it. It just seemed like if I was ever going to pitch on a yeast cake, a 1.12 RIS would be the thing to do it with. Should I only use 1/2 the cake maybe? I was thinking that I would risk infection if I messed around with this too much.

You could certainly rinse your yeast again. Divide it up into 3 containers, etc and then pitch 2 of those onto the RIS. Even if you rinse it there is no need to make a starter.

Like I said before, I wouldn’t see much of a problem pitching that BIG OL’ RIS directly onto the cake as is. Some may say that you will be overpitching, but I’m not a yeast expert so I can’t say for sure. My gut says you’ll be fine, but I’d wait to hear someone with more experience on the matter chime in. If it were me, on the big of a beer, I’d oxygenate my wort a crap load and put it to the pacman cake.

I just dump mine onto the yeast cake.

This fermentation will go crazy and get hot fast so keep a close eye on it. Do you have any way to control the fermentation temperature?

Yep, I have a chest freezer with a digital temp controller…so I think I can keep it in the low 60’s no problem.

I’m going to dump it right onto the yeast cake and let her rip. Thanks for all the help!!

Normally I oxygenate with pure O2 and a 2 micron stone for 60 seconds…would this kind of beer warrant maybe 2 minutes of O2?

2 minutes of O2 just before pitching, and then again anywhere from 4 hours to 24 hours later.

Can you tape the temperature sensor to the side of the fermenter? Tape some insulation over it and you’re good to go. Which temperature controller do you use?

cool…thanks. I use a Ranco digital temp controller. I love it, I can dial it in to ±1 degree…I think it has really helped me to get more consistent results.

Sweet. Tape it on, insulate it and set the differential to 1 degF and RDWHAHB.

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