1.017 Final gravity? Mash Temp from Brewfather prediction off

[benoj]

Hey all,

So I brewed what was supposed to be an AIPA-ish type beer a few weeks back. The fermentation started off well and has stopped showing signs of activity according to my tilt for the last few days. The tilt reading was pretty high, so I pulled a sample this morning..and well it was about what tilt said 1.017 a full 9 points higher than what my predicted FG from brewfather said.

Here are my fermentables:

Malts (4.177 kg)
3.4 kg (75.1%) — Crisp Clear Choice Malt ® Extra Pale — Grain — 3.7 EBC
500 g (11%) — Weyermann Munich I — Grain — 15 EBC
177 g (3.9%) — Wheat Flaked — Grain — 3.2 EBC
100 g (2.2%) — Simpsons Crystal Dark — Grain — 270 EBC
Other (350 g)
350 g (7.7%) — Candi Sugar, Clear — Sugar — 1 EBC

And I pitched 2 packets of San Diego super yeast and it's been in the fermenter for 10 days.


The thing is, with the above, Brewfather said my OG was going to be crazy low with the above (1.005 or so) so I bumped my mash temp until it hit an acceptable level to me 1.008 (because this brew was to use up the dregs of my grain stores I couldn't add more). However the mash temp was 70c(158f) and my strike water was a few degrees higher than that - which in hindsight felt way too high, but I didn't want a super-duper dry beer.

Do you think this seems like a stuck fermentation - or was the FG prediction from Brewfather way off given the mash temp it predicted?


SIDE NOTE: It's a very heavily dry-hopped and currently hazy beer - I'm thinking of just rebranding as a NEIPA and calling it a day

 

[madscientist451]

Brewfather said my OG was going to be crazy low with the above (1.005 or so) so I bumped my mash temp until it hit an acceptable level to me 1.008 (because this brew was to use up the dregs of my grain stores I couldn't add more).

OG=original gravity
The recipe above is for a 20L batch?
I'm thinking your original gravity was around 1.053? Yes, I would expect it to ferment a bit lower than 1.017. Any chance your mash temp was a bit higher than you were shooting for?

 

[benoj]

OG=original gravity
The recipe above is for a 20L batch?
I'm thinking your original gravity was around 1.053?

The OG was 1.061 as measured by my hydrometer (at room temp)

Yes, I would expect it to ferment a bit lower than 1.017. Any chance your mash temp was a bit higher than you were shooting for?

I use the SS Brewtech 1V BIAB which has a temp controller and I also used a thermo pen - so fairly confident it stayed in that range (although I have noticed some issues with wandering temps and the BIAB bag on the thermometer)

 

[rburrelli]

You specify the attenuation percentage of the yeast you choose in Brewfather. Nothing is automatic, as is the case with most brewing software. If your percentage is too high then your FG will be unrealistic.

 

[benoj]

You specify the attenuation percentage of the yeast you choose in Brewfather. Nothing is automatic, as is the case with most brewing software. If your percentage is too high then your FG will be unrealistic.

Thanks - I used the predefined value from BF and not had any issues with it being off by this amount so far.