Help me save my porter

[ampersat]

OG was around 1.060 and the yeast gave up around 1.030 (it was a wyeast that I built up a starter from). It seems to have a good yeast cake at the bottom though but little activity after a week.

Do I pitch more yeast? Do I stir up the existing cake? Do I hit it with some more oxygen? Do I do all of the above?

[beerking]

Start easy. Gently rouse the yeast, without aerating (do NOT add more oxygen).

Also, what is the temperature? It should be in the low to mid 60s. Anything less and your yeast might quit early.

Which yeast did you use?

[markaberrant]

I'm sure I responded this earlier this morning, guess my post didn't submit.

Gently rouse the yeast, put the carboy somewhere warm (say 72-75F), and forget about it for another week.

[ampersat]

Well, I suppose I should have checked back sooner. I'm using a pure oxygenation setup and ran that in the wort for a half a minute or so and gently stirred up the yeast bed. No response whatsoever from the yeast.

I think my problem was yeast vs. temperature; Wyeast 1968 has a low end of 64 degrees, which is the temp my brewing room settles at during the winter. I guess I'm going to have to start picking brews/yeasts that conform to the available temperature since I have little control over temperature currently.

Having said that, I racked the brew to another carboy, repitched using a starter built up with Danstar Nottingham, which would appear to perform well at my brewing temperature, and we'll see how it goes.

beerking: I'm curious about the oxygen comment. Since I'm using a pure oxy setup, why would blowing more into the brew be a bad thing?

[markaberrant]

If you add more oxygen after it's already started fermenting, you've just oxidized you beer, which leads to your beer going stale rather quickly and developing a "cardboard" flavour.

An ambient temp of 64F should be fine for fermenting with 1968, assuming you pitched healthy yeast. Remember that fermentation generates heat, so your beer will be fermenting warmer than 64F.

[corkybstewart]

.

beerking: I'm curious about the oxygen comment. Since I'm using a pure oxy setup, why would blowing more into the brew be a bad thing?
Luckily the oxidation will take a while to rear it's ugly head. Drink fast and you can get ahead of it. Or give it to someone you don't like that always wants to drink your "free" beer.

[BrewDog]

It's possible that the yeast will take up some of this oxygen if/when they re-activate, but just remember that the only time to add air/oxygen is after the wort is cooled post-boil and before you pitch the yeast. Other times can lead to the staling flavors described above (to varying degrees - there is ongoing debate about hot-side aeration).

HTH-