stout troubles

[sam c]

got an oatmeal stout on the go at the moment that seems to have stuck at 1.030.

i have tried rousing the yeast and also last night i pitched a packet of nottingham. this was re-hydrated in about 500mls of water and poured gently into the brew. i did not aerate it first.this seems to have had no effect. i havent taken another reading yet but there are hardly any bubbles going through the airlock.

by accident i mashed the grains at quite a high temp, if memorie serves me right i think it was around 69 c. now having read a couple of books i know that mashing at high temps produces a more full bodied brew so there for less fermenable sugars. (correct me if i am wrong) so my concern is that due to the high mash temp the yeast has already eaten up all the fermentable sugars which has left me with an extreemly high F.G. is this possible?

if yes is the answer i was wondering weather i could add extra sugar to up the abv and lighten the body a little? if so how would i go about working out how much extra to add which would be the equivilent of reaching a final F.G of about 1.014 or so?

hope somone is able to help,

sam

[196osh]

What was the OG of the beer?

What temperature were you fermenting at?

1.030 sounds high even with the higher mash temp.

[sam c]

think it was 1.053

fermented at 19 - 20 c

[196osh]

Thats a 40% attenuation rate, which is insanly low for Nottingham.

Hmmm, mabye the lack of aeration in the beginning has something do do with it, but Nottingham says it does not need to be aerated.

But I am not sure if you should at this point, try rousing again and leaving it for a few days.

[sam c]

the original yeast was windsor and the notingham was the second batch i added to try and get it going again.

so you dont think it could be due to the high mashing?

oh and it was pretty well areated when i first pitched the windsor

[mysterio]

A high mash temp won't cause more than a change of a couple of percent of attenuation so I wouldn't blame that, unless your thermometer wasn't calibrated.

Was the beer allowed to get cold while fermenting ? Did you rehydrate the Windsor and what method ?

The usual process to restart a stuck ferment is to make an ACTIVE starter with some dried yeast, i.e. make up a pint or so of wort, get the yeast active in there, pitch it in to the main batch at high krausen. Pitching in rehydrated yeast is useless sadly.

DON'T add sugar!

[sam c]

this is the recipe a varriation on vossy's.thanks

Fermentable Colour lb: oz Grams Ratio
Pale Malt 5 EBC 7 lbs. 8.5 oz 3420 grams 81.5%
Crystal Malt, Pale 60 EBC 0 lbs. 8.1 oz 230 grams 5.5%
Chocolate Malt 1050 EBC 0 lbs. 8.1 oz 230 grams 5.5%
Flaked Oats 0 EBC 0 lbs. 8.1 oz 230 grams 5.5%
Roasted Barley 1350 EBC 0 lbs. 3.0 oz 85 grams 2%


Hop Variety Type Alpha Time lb: oz grams Ratio
Golding Whole 6.1 % 90 mins 0 lbs. 1.3 oz 38 grams 100%


Final Volume: 19 Litres
Original Gravity: 1.051
Final Gravity: 1.014
Alcohol Content: 4.8% ABV
Total Liquor: 29 Litres
Mash Liquor: 10.5 Litres
Mash Efficiency: 80 %
Bitterness: 29.939777433184 EBU
Colour: 163 EBC

yes the windsor was rehydrated as per instuctions on the pack.

ive got some more yeast arriving this week sometime from barlet bottom but dont have any DME. could this be replaced by beer enhancer as i might be able to get some from wilko's tomorrow or just sugar? what do you mean when you say high krausen?

i dont think the beer would have gone below 19 c whilst fermeting. it has bee going for 8 days now and went mad on the first night. so much so that it poped out the bottom of my fermener and i had to release some of the pressure before going to work by taking out the airlock for 30 seconds.

one concern is how long do i have to sort this out as it has already been in there for 8 days?

thanks for the help so far everyone

[mysterio]

Just make the active starter like I said, that will probably sort it out

High krausen just means at the peak of activity when the starter looks active. It should be foamy and you'll see bubbles rising.

Beer enhancer will do in a pinch, DME is ideal though. Don't use sugar, it is has no free amino nitrogen or other nutrients the yeast need, also the yeast won't produce they enzyme they need to breakdown maltose in the wort.

Give it another good rouse while you wait for the yeast, get in there with a big sanitized spoon or paddle and dont be shy with it, as long as you're not splashing and making foam you'll be fine.

As long as you were careful with sanitation the beer will be fine for a couple of weeks, maybe more

[Jymbo]

I used Windsor a few weeks ago and it stuck at 1017 - tried repitching with S-04 to no avail. Never had a stuck fermentation before that - won't be using Windsor again. TBH I wouldn't have though Windsor would have been a great choice for a stout in any case - too fruity.

[sam c]

thanks for the replies again guys.

im off to give it a good stir now.

the reason for using the windsor is that i thought the strong stout flavours might not let the yeast shine through that much. didn't really think about it that much to be honest.

just one more thing. how long should i be waiting for the yeast starter to be at high krausen? are we talking a couple of hours or a day? and just to check i dont need to add any beer enhancer or DME to the starter if i dont have any?

thanks again

[sam c]

im a little confused now having read another thread which said to sprinkle the dried yeast onto the beer, wait 15 mins and then stir it in. ive got the yeast now and some yeast nutrient but no DME to put in the starter, is this ok?