Slow Ferment

[ksbrain]

Brewed a Red on Sunday. Nothing too crazy. OG 1.070, total 2# or various crystal malts, mashed mid 150's, plenty of late hops, repitch of US-05 from the IPA brewed a month ago and kegged on brew day. I made an IPA also on Sunday with the same yeast.

Both are fermenting side-by-side in my fermentation fridge at 63F, according to a probe taped to the side of the carboy full of Red. The IPA had a nice chunky ferment with all the flakes moving up and down for a few days. But the Red was more subdued. It made a nice krausen, but never really got that chunky look.

Now the IPA is settled down and the Red is still lackluster looking.

So I took a gravity reading on the Red. It was about 1.056. Ugh. Fermenting, but slowly.

I've turned up the temperature in the fridge, and I'll wait it out a few more days, but I'm wondering if I ought to pitch more yeast. Could be that the second half of the harvest, which went into the IPA, had all the good yeast...

I guess if I were to pitch more yeast, I'd have to make a starter (possibly using the partially fermented beer itself)?

Any thoughts?

 

[Homebrewtastic]

Don't repitch recently used yeast. There's probably not enough healthy cells in there. That doesn't exactly explain why one is fermenting well with the same yeast and the red isn't. But more than likely that's the reason why.

Anytime I'm harvesting yeast I always make a starter. Same as if I were taking yeast fresh from the vial or smack pack. You need to get that healthy cell count up.

 

[Runyanka]

Did you wash the yeast prior to repitching? As stated above don't repitch, just wait it out.

 

[Homebrewtastic]

I think my first post might have come off as contradictory to itself.

What I mean is that you shouldn't pitch yeast directly out of a fermented batch unless you're skimming the yeast off of the top during high - krausen (because at high krausen you know the cells are much healthier).

The cells at the end of a ferment are tired, and worn out. If you're just grabbing some of the yeast off of the bottom of the fermenter you're probably throwing in a lot more unhealthy yeast than healthy yeast. So the best thing to do at this point is to make a starter. That gets the healthy cell count up.

But honestly if you're using dry yeast you're better off money wise just buying a couple of new packets and pitching those.

Also it's never advised to pitch directly onto a yeast cake. It's way too much yeast, and unhealthy yeast to bootl

 

[ksbrain]

Usually I rinse the yeast and store it for weeks or even months before reusing, without a starter. It takes a while to get going, but then goes normally and finishes in a timely manner. So this is out of the ordinary for my routine. And I admit my routine is very slackerish.

This time I rinsed it right out of the fermenter and pitched it from there. If anything, having not stored the yeast in the fridge for weeks after rinsing should increase the viability of the pitch, I'd think.

There must be some difference between the first cup poured off the rinse container and the second cup poured off the rinse container. Maybe it has something to do with the gelatin that I used in the batch whose yeast I harvested...

I swirled up the carboy a little and turned up the temperature a few degrees to 64F. I'll re-check the gravity in a few days and see what's next.

I have been thinking about just spending the $3 each time for a fresh pack of US-05, because most of the time for me the starter thing just doesn't happen.

 

[ksbrain]

I just checked gravity again and it is down to 1.032. Still high, but at least it's moving. The temp is up to 67 I think. It's got two weeks to finish out. I think it should, because I'd be OK with 1.020. But I might not have time to cold crash and gelatin at this rate.