Final Gravity

[scurry64]

I used the Brewer's Friend recipe calculator for a Pecan Stout recipe I plan to make and there seems to be an issue with the estimated final gravity. I suspect it's too high.
I tried calculating it with 1 and 2 packets of Nottingham English ale yeast, but it doesn't change the FG. I suspect the issue involves the estimated attenuation. The manufacturer's estimate is 65%. If this a reasonable estimate, it should I expect a higher attenuation?

 

[grampamark]

At 65% attenuation you would take out 44 gravity points. So, .068-.044=.024. I use Nottingham a lot and see 75-80% attenuation. Lallemand’s current data sheet doesn’t give an expected attenuation number, it just describes attenuation as “high”. The Beersmith database shows an expected range of 73-77%.With an OG of .068 I would expect a FG of .014-.016 using Nottingham.

 

[scurry64]

At 65% attenuation you would take out 44 gravity points. So, .068-.044=.024. I use Nottingham a lot and see 75-80% attenuation. Lallemand’s current data sheet doesn’t give an expected attenuation number, it just describes attenuation as “high”. The Beersmith database shows an expected range of 73-77%.With an OG of .068 I would expect a FG of .014-.016 using Nottingham.

That makes perfect sense. Thanks for the explanation. I'll cut back on the fermentables a bit because I don't want a ~7% abv. I appreciate your help.

 

[Elric]

One important thing you are missing in your details here is the mash temp As brewers friend takes that into account for final og as well. If your mash temp on the recipe was up at the higher end (and with this being a sweet stout it could be), it would explain why it is showing such low attenuation.