Stuck fermentation?

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Stuck fermentation?

Post by Leard » Thu Mar 22, 2018 11:14 am

I'm brewing a milk stout and have been aiming for quite a high FG. My OG was estimated as 1.056 however I managed to achieve 1.061. Rather than go for a bigger batch I decided to take it as it was and not top up post boil.

Anyway after two weeks of fermentation it seems to have gotten stuck at 1.020. However my estimated FG according to Beersmith should be 1.016. I have an attenuation measurement of 65.9% when it was estimated to be 69.8%.

Is the FG predicted by Beersmith based on the estimated OG or the actual OG? Because if it's based on the estimated OG then fermentation is probably done. If not there's still a few more points to go.

I used Safale US-05 yeast. Reckon I'm good to bottle?

Hollow Legs
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Re: Stuck fermentation?

Post by Meatymc » Thu Mar 22, 2018 3:58 pm

Interesting. If you have a look at Scraggy's Milk Stout post in the Grain section you'll see he's also concerned at being at 1020 as well. I'm no expert but wouldn't be overly worried at being only 4 points off target given a 1061 starting point.

Even further under the Table
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Re: Stuck fermentation?

Post by Rookie » Fri Mar 23, 2018 12:42 am

Recipe please.
I'm just here for the beer.

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Re: Stuck fermentation?

Post by McMullan » Fri Mar 23, 2018 6:04 pm

We do seem to rely, almost religiously, on software too much these days. Fake software :lol: The output is always a guesstimate. I often find stouts finish higher than predicted by software. I'd be interested how they predict the unpredictable, fermentability of an unknown wort. Whenever I do a stout I do a forced fermentation test. You could leave it where it is for another week or so, Leard. It might drop another point or two. It probably would drop further in a secondary for several weeks. It might not. If it tastes good and goes bright, it's done. Assuming you pitched in good wort and pitched sufficient healthy yeast, there's not much to suggest anything has gone wrong here, to be honest. Extra time is what would squeeze out a few more points.

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