# Yeast failure to thrive



## knucklehead (9/3/15)

Greetings all,
Long time listener first time caller....

Anyway I have a brew that just refuses to start fermenting and I am out of ideas.

The rough details are the brew is an all grain, sweet oatmeal stout that I have made many times before. I hit the target gravity of 1085. Cooled the wort and pitched my 34/70 yeast (1ltr starter).
After three days the gravity was still at 1085. I moved the fermentor into a warmer spot and waited another 48 hours. Still stuck at 1085.

So I prepared a fresh yeast starter and repitched. 3 more days go by and gravity is still at 1085.

What could I have done to this batch that would make it so unwilling to ferment?


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## Yob (9/3/15)

Same batch of yeast?

Was it an active starter? Changed colour, developing foam?


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## knucklehead (9/3/15)

Yes same yeast both times (safale 34/70).
Both starters looked very healthy prior to pitching. Lots of foam etc.
The wort has not changed colour or smell. No foam or activity noticable at all. Its a waste land!


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## Yob (9/3/15)

Get a different yeast as fast as you can I guess, I assume both packs were in date?


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## manticle (9/3/15)

Why are you using a dry lager yeast starter on a high gravity stout?
What temp is the brew at?

Aerate the brew as much as you can while you prepare another, appropriate starter of healthy, active yeast. The 34/70 may kick off but you've most likely way underpitched. How did you prepare the starters? New yeast? Old yeast? Packet? Slurry?
1 L is not enough for 1.085.


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## knucklehead (9/3/15)

I can't really justify the 34/70 yeast except I used it before and had good results. So didn't change.
Same reason I only did a 1 litre starter.

Temperature is currently about 22c. I normally get good results around 15c but have been slowly increasing temp to try and get things moving.

O.K. so I think what you are saying about under pitching is ringing true.
Different yeast is also a good idea. I have used SAF33 before but that’s just because the bloke at the homebrew shop said it would be good.
What If I did a 5 litre starter with 1kg of DME, that should give a SG around 1040 -1050. Once this is vigorously fermenting it gets added to the stout.


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## Yob (9/3/15)

100g/L is a 1040 wort. (5L = 500g)


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## knucklehead (9/3/15)

Wow...... wrong yeast, under picthed and my gravity calculations are 100% out, and the beer still tastes O.K.

Should be able to turn out a pretty good drop once I have some idea of what I'm doing!

Thanks.


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## panzerd18 (10/3/15)

My last batch I pitched two packets of W34/70 into 12c wort with a sg of 1.040. The lag time was over 3 days for it to ramp up to high krausen, so a long lag time.


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## knucklehead (11/3/15)

Just a quick update.

Made 5 litre starter at 1040 and 2 packets of mangrove jack British ale yeast (M07). Once this was fermenting strongly it was added to the lazy stout.
While it is still early days the whole thing looks and smells like its going great guns. Haven't taken a gravity reading yet, too scared to disturb it.

Thanks for you advise, you may have just saved my brew.


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