Porter high OG with fermentation stopping at 1.030?

Question

I was doing a porter/stout with extract and also steeped milled smoked malt for a more smokey flavour as part of the process (steeped in warm water around mashing temperature for about 20 minutes before filtering out and adding it to the boil). (OG was 1.120) I fermented with Safale US-05.

Additionally after boil finished I added vietnamese coffee. Also one of my bags of hop pellets broke and some of the pellet residue got into the primary fermenter.

Today I tasted the beer and doesn't taste sweet, however the FG is now at 1.030. Wondering if this is stalled fermentation. Is it possible the beer is finished (based on my calculation the alcohol level should be 11.8% where Safale US-05 has max tolerance of 12%).

Is my beer finished fermenting or not (might be my OG and FG were higher due to the hop pellet residue and coffee?). I plan to leave it to climb from the 24 degrees it was fermenting at to 28 degrees?

Answer 1

Seeing that:

• US-05 has an apparent attenuation between 73% and 77% (Fermentis data sheet)
• You start from an OG of 1.120
• And it is an extract beer (always more difficult to attenuate)

I would conclude that your fermentation is finished. The calculated attenuation is now 75% which is nice in the middle of the expected attenuation of the yeast. You could possibly nibble off some extra points with letting it rest and increasing the temperature.