Stagnated Fermentation?

[the_yobbo]

G'day,

I've got a coopers dark ale mix using a stout enhancer kit for fermentables. The initial SG was 1043 and it has sat on 1018 for about 5 days now. 1018 seems a bit high to have completed fermentation.

It was fermented at 18 degrees. I tried heating it to 20 degrees with a little swirl of the wort but no change. I've given it a more rigorous swirl since and yet to take another reading.

Is 1018 too high for a FG?

 

[Pennywise]

What volume did you make it to? What yeast and how much? Do you know what's in this stout mix?

 

[buttersd70]

Do you know what's in this stout mix?

Thats the clincher.

Without knowing what's in the stout mix, theres no way of telling how low it should go....different adjuncts ferment to different degrees...being a stout mix, I would say that it's likely there are quite a few unfermentable (or low fermentable) sugars in there. If it had a couple of hundred grams of lactose in it (which wouldn't be particularly unusual for a stout mix), then 1018 is certainly in the realms of the probable.

If in doubt, take 300-500 mL of wort out into a sanatised pet bottle....shake the absolute crap out of it, to get it all aerated, put the cap on (loosely, not sealed), and put it somewhere nice and toasty for a few days, high 20's if possible (or even low 30's)....shake it vigoroulsy whenever you walk past it....get lots of oxygen in there.....

After a few days, cool it down to 20C and take a hydrometer reading. That should be as low as it will possibly go. Discard the sample.

Whats in your fermenter should end up at, or just over (within a couple of points) of where this sample ends. If theres a real big difference, then fermentation is stuck. If not, it's finished.

 

[manticle]

Nice trick. I'll be keeping that in mind as I have had a few partials finish very high (still well drinkable, high gravity to start and no bottle bombs at all).

 

[the_yobbo]

If in doubt, take 300-500 mL of wort out into a sanatised pet bottle....shake the absolute crap out of it, to get it all aerated, put the cap on (loosely, not sealed), and put it somewhere nice and toasty for a few days, high 20's if possible (or even low 30's)....shake it vigoroulsy whenever you walk past it....get lots of oxygen in there.....

After a few days, cool it down to 20C and take a hydrometer reading. That should be as low as it will possibly go. Discard the sample.

Ooh, that does seem a damn good idea. Will carry out the proceedure this evening.
Thanks for responses.
And no, I don't know what is in the stout mix Will find out at some stage.
For the record, 1 packet of S-04 and 23L as per the coopers can instructions.

Additionally, after the more rigorous swirl of the fermentor, it looks like it has dropped down a point or two. I'm surprised that with all my reading, something as simple as giving the fermentor a simple shake isn't mentioned more often. I'm thinking of adding a fermentor swirl to my standard brewing system when airlock activity has slowed.