Reusing yeast

[Rob Martin]

I reused yeast yesterday, first time in just shy of 100 batches. This second batch is not taking off as quick as I'm used to, and am wondering if I'm too nervous or if something is wrong.

First batch:

Yeast: Wyeast 1056. Brewed a cream ale on 8/27. OG 1.048. F.G. 1.012, attenuation 74%. 21 days in primary. Only used primary, generally around 72 degrees.

We kegged this beer Saturday straight from primary. When we got down to the yeast slurry, I poured it into a sanitized (Starsan) plastic bucket with lid (old 5 qt ice cream container). There was approximately 2 qts of yeast slurry. It sat in this for 2-3 hours until we were done brewing our next batch.

Second batch:

Citra lemongrass rye. OG. 1.054. When the wort was cooled to 80, we pumped it into the same fermenter, but cleaned with PBW and then sanitized with Starsan. When transferring, we use our pump with a wand on the end of it. The tip is pinched, so it aerates really well when being pumped into fermenter, especially when we hold it up above the liquid level in fermenter. We'll get a 4" foam from just pumping because it is shooting into the fermenter so vigorously. I then oxygenate with pure O2 for 2 minutes at approximately 5 PSI.

Normally, for an ale of this OG, I would do a 4-step starter.

Wed AM. Smack pack
Wed PM. 850mL - 1 L starter.
Thurs PM - 1 additional L added to starter, 2 L total
Fri PM - 2 additional L, 4L total for starter.
Brew Saturday AM, decant spent wort, pitch slurry only Sat. PM.

Using my normal yeast step, I have had at times active, visible fermentation before going to bed Saturday night, but almost always it's going Sunday AM. With this reused yeast slurry, I do not see active fermentation yet after 22 hours. Pitched at 78 deg, it's 74 deg currently.

[JMcG]

I think that the yeast cake is just dormant and will wake up and start eating by tomorrow.
jim

[Rob Martin]

Little paranoia on my part, it's burping now, 27 hours later. This is a fairly long lag time from what I'm used to. Any suggestions on reusing yeast, or is this pretty typical?

[JMcG]

My experience has been that there tends to be a lag time prior to onset of active fermentation if you pitch the yeast straight from another fermentation.
If you let the previous beer slowly finish and let the yeast clean up and get rid of some of the off flavors (e.g. diacetyl) it tends to slow down metabolism and it starts to shift into a dormant phase. If given fresh wort it wakes back up, but it takes a day or so.
I've been able to "wake up" the yeast by adding fresh wort to the cake a day or so prior to re-pitching.
jim

[Rob Martin]

Thanks Jim. It's going pretty strong now, probably a little too hot as well. Trying to get it to cool down with various means.