Help Troubleshoot my low FG

[BrianDorry55]

Long story short, I have gotten to the point where I'm usually nailing my original gravity...Which is great, there was a while where I struggled with this. I make beer that I really like and I'm usually very happy with it. Today I went to keg an american pale ale that I brewed a few weeks ago and the final gravity was 1.008 (target was 1.014). Which brings me to my issue. I'm overshooting my final gravity pretty regularly. I used to not care because the beer was always good and hey, "more alcohol, right?"...but now that I am focusing on entering competitions and really dialing in my processes, so it bothers me that I'm not ending up with exactly the beer that my recipes are intended to create. I would really appreciate any input into why I might be overshooting my FG. I will describe my system and the most recent recipe and mash process below.

Mash tun: Your basic gatorade cylindrical cooler conversion mash tun

Grain Bill for this recipe (6-gallon batch - pale ale):
6.5 lb - 2 row
4.25 lb - Pilsner
1.25 lb - Flaked wheat
0.5 lb - Crystal 40
0.5 lb - Carapils
0.25 lb - Victory

Mashed for 1.5 hours (usually mash for an hour but got busy while this was going) at 152 degrees.

Intended OG: 1.056
Intended FG: 1.014

Yeast: Wyeast 1056 American Ale at low temps 59-62 ambient
First day was kept around 70 degrees to let things kick off

Actual OG: 1.056
Actual FG: 1.014

Based on these numbers, attenuation was 85%, even though Wyeast lists attenuation for this yeast at up to 77%

Anyone have any input they can add? The beer tastes great! But I still want to figure out how to hit my intended numbers. Thanks!

 

[RM-MN]

Long story short, I have gotten to the point where I'm usually nailing my original gravity...Which is great, there was a while where I struggled with this. I make beer that I really like and I'm usually very happy with it. Today I went to keg an american pale ale that I brewed a few weeks ago and the final gravity was 1.008 (target was 1.014). Which brings me to my issue. I'm overshooting my final gravity pretty regularly. I used to not care because the beer was always good and hey, "more alcohol, right?"...but now that I am focusing on entering competitions and really dialing in my processes, so it bothers me that I'm not ending up with exactly the beer that my recipes are intended to create. I would really appreciate any input into why I might be overshooting my FG. I will describe my system and the most recent recipe and mash process below.

Mash tun: Your basic gatorade cylindrical cooler conversion mash tun

Grain Bill for this recipe (6-gallon batch - pale ale):
6.5 lb - 2 row
4.25 lb - Pilsner
1.25 lb - Flaked wheat
0.5 lb - Crystal 40
0.5 lb - Carapils
0.25 lb - Victory

Mashed for 1.5 hours (usually mash for an hour but got busy while this was going) at 152 degrees.

Intended OG: 1.056
Intended FG: 1.014

Yeast: Wyeast 1056 American Ale at low temps 59-62 ambient
First day was kept around 70 degrees to let things kick off

Actual OG: 1.056
Actual FG: 1.014

Based on these numbers, attenuation was 85%, even though Wyeast lists attenuation for this yeast at up to 77%

Anyone have any input they can add? The beer tastes great! But I still want to figure out how to hit my intended numbers. Thanks!

The red items are something to look at. Brewing all grain should give you good control of body in your beer as you can change out the mash temp to add or subtract body. Carapils is a way to add body. You really shouldn't need it.

With the standard mash tun, the mix of fermentable and unfermentable sugars is controlled mostly by mash temperature but with a coarser crush the longer mash time will allow the beta amylase more time to break down some of the otherwise unfermentable sugars. That is part of the problem.

Much of the fermentation happens in the first couple days. To have some control over what the yeast do you need to keep the beer cool during that time. You don't need to keep the beer that warm during the first day and doing so will not help your problem. Chill the wort to a temperature lower than you intend to keep it at during the fermentation and let it warm to that temperature after you pitch the yeast. Once the fermentation starts the yeast activity will warm the beer and by starting it warm that activity will make it difficult to bring the temperature down quickly enough and the yeast will tend to over attenuate.

 

[AMessenger]

I've been frustrated by this too. I had a beer that got to 63% apparent attenuation after a month (which was my target) and then proceeded to get down to 94% AA given 4 more months in secondary (I was pissed). Yeast are odd creatures that don't care what we want them to do.

It seems like you'd have to brew the same beer multiple times to really understand how the yeast will behave in your particular wort. Adding in variability of yeast heath, pitch size, and intergenerational yeast behavior and the problem seems much more complicated.

One more idea to consider: how much does 6 gravity points matter. May not make that much of a difference to the final product:

http://brulosophy.com/2015/10/12/the-mash-high-vs-low-temperature-exbeeriment-results/

 

[BrianDorry55]

The red items are something to look at. Brewing all grain should give you good control of body in your beer as you can change out the mash temp to add or subtract body. Carapils is a way to add body. You really shouldn't need it.



With the standard mash tun, the mix of fermentable and unfermentable sugars is controlled mostly by mash temperature but with a coarser crush the longer mash time will allow the beta amylase more time to break down some of the otherwise unfermentable sugars. That is part of the problem.



Much of the fermentation happens in the first couple days. To have some control over what the yeast do you need to keep the beer cool during that time. You don't need to keep the beer that warm during the first day and doing so will not help your problem. Chill the wort to a temperature lower than you intend to keep it at during the fermentation and let it warm to that temperature after you pitch the yeast. Once the fermentation starts the yeast activity will warm the beer and by starting it warm that activity will make it difficult to bring the temperature down quickly enough and the yeast will tend to over attenuate.

So I think starting fermenting a little warm to give the yeast a head start could potentially be my issue...because that’s something I do regularly. I never get any apparent ill effects like Fusel alcohols from fermenting too warm (because I tend to switch to the lowest suggested ferm temp after a day) but I overattenuate everything (and I’m using a single smack pack to ferment everything, almost never making a starter).

I considered the longer mash, but this was an anomaly and wouldn’t I have had a higher OG if this was the cause?

Would Carapils make my wort any more fermentable? I realize a lot of people think it’s unnecessary...it may have helped me in this since I ended up with a drier beer than I wanted.

 

[SanPancho]

Longer mash skews your sugars towards fermentables as opposed to non fermentable. All other things equal it gives lower FG.

Carapils should add non fermentables. Its not the problem.

 

[RM-MN]

I've been frustrated by this too. I had a beer that got to 63% apparent attenuation after a month (which was my target) and then proceeded to get down to 94% AA given 4 more months in secondary (I was pissed). Yeast are odd creatures that don't care what we want them to do.

It seems like you'd have to brew the same beer multiple times to really understand how the yeast will behave in your particular wort. Adding in variability of yeast heath, pitch size, and intergenerational yeast behavior and the problem seems much more complicated.

One more idea to consider: how much does 6 gravity points matter. May not make that much of a difference to the final product:

http://brulosophy.com/2015/10/12/the-mash-high-vs-low-temperature-exbeeriment-results/

This was probably caused by a wild yeast that you picked up when you transferred your beer to secondary.

 

[Lefou]

Two obvious notables here.
A large percentage of you grain consists of base malts which increases your diastatic potential. Allowing your mash to rest an extra half hour before mash-out gives those enzymes more time to create a more fermentable wort. I tend to do this intentionally to help create a drier, crisper ale that has a marginally higher ABV. Some malts are simply more modified than others, US brands sometimes more so than imports.
I tend to favor an attenuated, drier beer when matching it with starchy foods.

A couple methods to reduce attenuation....
Darken your beer slightly with less modified base malts and/or the non-crystal toasted specialty malts such as biscuit, Victory, or even Special B. Reduce your percentage of diastatic base malt as well. Use a single-step infusion mash a couple degrees higher than 152F.
Couple this with a less attenuative yeast and it may help. It may necessitate changing the styles, but unless you're looking to create a specific style with narrow requirements, it's not really an issue.