1318 stopped fermenting. give it another chance?

Hi,
3 months ago I made an IPA with London Ale 1318 and came out perfect (worked from 1062 to 1014). I recycled the yeast and a month ago used it for a stout. The stout was ment to prepare a yeast cake for an imperial porter.

The stout was in my cellar at 18°C (65°C) but the temperature dropped unexpectedly to 16°C (62°F). I found the beer at 1021, so I brougth in my house for two weeks at 20°C (68°F) but nothing happened. The beer tastes young but fine.

My thougths are that the yeast should have restarted working (or even not stopped working). The fact that it's not, could tell that my recycling process was not good (even if I made it without problems many times).

Now I need a suggestion for my incoming imperial porter (predicted OG 1093):
1) should I try the yeast cake anyway;
2) should I make a big starter with a pack of 1056 american ale that I have left in the fridge;
3) or should I throw away the recycled 1318, temporarily put apart the imperial porter idea and use the 1056 yeast for a different recipe?

Thanks in advance,
cheers
Piteko

First off, have you tried stirring/agitating the yeast cake back into the stout? British strains of yeast are very flocculent, and once they drop out of the beer they won't do much more unless you work them back into solution. You could add a bit of nutrient at the same time; I've gotten stalled fermentations with British ales to attenuate more this way. A month down the line may be too much for them to just take off again, but it's worth a shot.

If this doesn't work, I would make the yeast cake into a slurry, put it in a small-ish container (say, 1 gallon), and then put a fairly strong starter on it. Oxygenate it well, add yeast nutrient, let it grow a little while at approx. 70F, agitating occasionally (if you don't have a stir plate). I would be surprised if it doesn't re-start.

Ideally, you could pitch this during high krausen; I'm not sure I would cold crash it before pitching; the yeast have gone through enough already. This procedure will save you a yeast pack, and will also necessitate a smaller starter - and hence less starter wort in the beer - as you're just trying to wake the yeast up, not multiply it.

To avoid off-flavors, I would ferment at pretty low temps to start - around the 65F range you were shooting for with the stout. But this time, when primary just starts to slow down, heat it up (gradually, if possible; abruptly, if not) to about 68-70F or even a bit higher. This will help attenuation, keeping the yeast going, and it won't add significant off-flavors as the most violent stage of fermentation is already past.

Skyforger said:

First off, have you tried stirring/agitating the yeast cake back into the stout?

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Yes. I sanitized a long spoon and stirred slowly to avoid oxidation but for more than a minute, so I'm sure the cake was back in solution.

Skyforger said:

You could add a bit of nutrient at the same time; I've gotten stalled fermentations with British ales to attenuate more this way

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I can't since I don't have any nutrient and buy it would take me at least 2 weeks.

Skyforger said:

If this doesn't work, I would make the yeast cake into a slurry, put it in a small-ish container (say, 1 gallon), and then put a fairly strong starter on it. Oxygenate it well, add yeast nutrient, let it grow a little while at approx. 70F, agitating occasionally (if you don't have a stir plate). I would be surprised if it doesn't re-start.

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I'm pretty sure it will restart. My deeper doubt is about the FG the yeast will be able to reach. Since this was an easy batch, I'm worried about the attenuation on a big beer.

Skyforger said:

Ideally, you could pitch this during high krausen; I'm not sure I would cold crash it before pitching; the yeast have gone through enough already. This procedure will save you a yeast pack, and will also necessitate a smaller starter - and hence less starter wort in the beer - as you're just trying to wake the yeast up, not multiply it.

Click to expand...

Using a smaller starter in high krausen is a simple and good idea. I always used big starters to multiply the yeast and I realize that without this suggestion I would have gone by the same path.

Skyforger said:

To avoid off-flavors, I would ferment at pretty low temps to start - around the 65F range you were shooting for with the stout. But this time, when primary just starts to slow down, heat it up (gradually, if possible; abruptly, if not) to about 68-70F or even a bit higher. This will help attenuation, keeping the yeast going, and it won't add significant off-flavors as the most violent stage of fermentation is already past.

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Now that you told it, I took another look to the IPA fermentation temps and I realized that happened just the same: primary temp at 65F and the secondary fermentation temp unintentionally raised up to 74F .

I putted the stout in the basement because I knew that only with the fermentation the temp would have risen from 64F to 68F. If I kept it in the house at 68F it would have risen from 68F to 74F. But at the end of primary fermentation the basement temp fell down to 62F, at the same time I got sick and moving 6 gallons up to two floors was just the last thing I could think of

So you think that even if now the yeast isn't waking up again to eat the last few points, if I wake it with a small starter, pitch in krausen and raise a bit the temp after the peak of fermentation, the yeast would do the job from 1093 to 1023?

Many many thanks Skyforger for your interesting suggestions
Cheers from Italy
Piteko

If you don't have any yeast nutrient, dry bread yeast is packed with nutrient for yeasts. You can boil a bit in some water. This will kill unwanted yeast, and leave a nice, highly nutritious soup. Just don't skip the boil; the last thing you want is that vigorous bread yeast taking over.

But yeah. If you try to complete primary ferment in a cool area, the fermentation warms up the beer for the first part. When it dies down, it cools down - essentially mildly cold crashing the yeast before fermentation is complete. Some yeasts can tolerate it, some can't.

Getting the gravity down from 93 to 23 would require an attenuation of nearly 80% - theoretically possible with this yeast, but perhaps not to be counted on. Specialty strains exist for high-gravity beers, but honestly I'm not sure how much better they would do than this strain, if in good numbers and pitched at high krausen. It has pretty high attenuation, at least in theory. I would give it a shot.

High-gravity beers need some TLC to finish out properly. Wyeast's champagne strain is often used to finish off barleywines, for example. If you don't get the attenuation you want with the primary strain, you can add some champagne yeast and keep it at fairly high temps (say, 75-80F) to finish it off. Since it's such late-stage fermentation, and since the beer is so strong, it shouldn't add any noticeable flavor or aroma.


Prost from the Great Lakes! May your fermentations be strong and your drinks healthy and happy.

Skyforger

Skyforger said:

If you don't have any yeast nutrient, dry bread yeast is packed with nutrient for yeasts.

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Very very nice idea. I'll look for it.
I wonder if a very common product here in italy has the same nutrients. It's literally called "beer yeast" and it's used for bakery, but it's not dried:

Skyforger said:

Getting the gravity down from 93 to 23 would require an attenuation of nearly 80%

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Yes, it's 75% but I think I'm too positive with that
Wyeast spreadsheet tells that this yeast should finish in a range of 71-75%. There's no problem for me. A tripel I just made with #3787 started from 1083 and gone to 1011. Damn 87%... Fermented slowly for 5 weeks. The stout, probably because of the mild cold-crush and because maybe had a less fermentable worth, stopped at 59%. You don't really know what you can expect...

Wait, I could:
- move the stout off the london ale III cake in a secondary fermenter;
- clean the london ale III cake for the incoming imperial porter;
- add to the stout in the secondary some trappist high gravity. Maybe with a little starter. Now I'm worried it could finish too low

Skyforger said:

High-gravity beers need some TLC to finish out properly.

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I have to say I looked online too but I cannot understand what TLC stands for

Skyforger said:

Prost from the Great Lakes! May your fermentations be strong and your drinks healthy and happy.

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This is a shot of my trappist high gravity #3787 yeast: :rockin:
and this is my london ale III yeast:
Cheers!
Piteko

TLC = tender loving care

rod said:

TLC = tender loving care

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LOL, thanks for the explanation
Cheers!
Piteko

piteko said:

Wait, I could:
- move the stout off the london ale III cake in a secondary fermenter;
- clean the london ale III cake for the incoming imperial porter;
- add to the stout in the secondary some trappist high gravity. Maybe with a little starter. Now I'm worried it could finish too low

Click to expand...

UPDATE to the stout and the imperial porter:

- moved the stout and pitched with the trappist high gravity. Finished at 1011 and it's fine, no strange flavours came in from the belgian yeast;

- cleaned the london ale III cake and fermented the imperial porter: started at 1093 and stopped at 1032 (66% attenuation, 8% ABV). Bottled a pair of bottles with this as a test and putted the rest with some trappist high gravity, it's almost 8 weeks that is slowly slowly fermenting...

Cheers!
Piteko