Yet another stuck ferment

[TheDudeAbides]

Hi everyone.
Made a small batch of stout with my partner as her first go at homebrew.
OG was quite high - 1.073 - but I had expected that given the ingredients and Beersmith's prediction.
Fermentation seems to be stuck with an SG reading of 1.034.
The fermenter was kept at a good steady temperature of about 22 degrees.
Yeast used was Brew Cellar English Ale, which is similar to S04. About 36 hours ago, I pitched another packet. SG has not dropped, nor has there been any noticeable activity or krausen.

I seem to be always having a similar problem whereby no matter what type of brew I'm doing, how much the batch is, or what yeast I use, I can never knock more than 38 points off the OG. At the moment, 1.034 is completely unworkable.
Any ideas…?

Batch size was 11L. Grains were steeped first, and enough DME added to bring pre-boil volume to 1.040. Other fermentables were added after the boil.
Here's the ingredients:
0.35 kg Roasted Barley
0.50 kg Dark Dry Extract
12.00 g Cluster
0.25 Items Whirlfloc Tablet
25.00 g Willamette
1.0 pkg SafAle English Ale (DCL/Fermentis #S-04) Yeast
100.00 g Cacao nibs
5.00 g Liquorice Extract
1.50 kg Thomas Coopers Dark Malt Extract
0.25 kg Corn Syrup

 

[manticle]

You do have a lot of unfermentables in there. Additionally you have used a yeast that is notorious for stalling AND it seems as if you may have underpitched into a high gravity brew.

Check this article for tips - look especially at the fast ferment test and the recommendation fror making an active starter rather than just throwing more yeast at it.

http://www.aussiehomebrewer.com/articles/article130.html

Also, I can't see a real need for whirlfloc in an extract brew.

 

[TheDudeAbides]

Thanks for the reply Manticle.
I guess I misunderstood what whirlfloc was for. I thought it was just to give a clearer beer, regardless of ingredients. I'll save my dollars in the future.
I've read the article, and worked through the steps, but the gravity hasn't budged.
And now that I've done a bit more research, I realise that I misunderstood what maltodextrin (corn syrup) will do to my beer. I was under the impression that it was fermentable. Can you confirm for me that I was mistaken?
Also, should I be bottling a brew with an FG of 1.034?
Cheers for the help.

 

[manticle]

So you tried the fast ferment test? That suggested 1034 as well?
You've added an active starter to the brew (not just more yeast)?

maltodextrin is only partially fermentable - about 20-30 percent from memory. It is used to add body to the brew - body comes from dextrins (longer chain sugars that are not fermentable with regular brewer's yeast) and proteins.

I hesitate to say 'yes bottle away' but looking at the ingredients in an 11 litre batch, I wouldn't be too surprised.

so long as you tried all the steps as specified, I would suggest bottling into PET, keeping the bottles outside and either individually wrapped or at least with a few blankets over the box. See how hard the bottles get and how quickly - if they start to swell or appear overcarbed when you open them, refrigerate the lot, give them some degassing and drink quickly.

Easy to confuse corn sugar (dextrose, totally fermentable) and corn syrup (maltodextrin -70/80% unfermentable) especially when corn syrup here is different to corn syrup USA.

 

[pat86]

1034 sounds awfully high, I guess you already re-pitched and it isn't cold but 1034 is closer to a starting gravity than a F.G. !

 

[manticle]

Yes but it depends on a number of factors. You can start gravity anywhere - 1.030, 1.050, 1.170 - yeast can only deal with what they have been given