• Welcome to the new forum! We upgraded our forum software with a host of new boards, capabilities and features. It is also more secure.
    Jump in and join the conversation! You can learn more about the upgrade and new features here.

This is not the same old FG question people ask

raysmithtx

Apprentice
Joined
Oct 3, 2012
Messages
4
Reaction score
0
I have happily used Beersmith for over 60 batches and am quite happy with the results.... but I have a nagging issue I can't seem to resolve.

When I duplicate a recipe I find on the web Beersmith almost always predicts OG and IBU to perfectly match the copied recipe. The problem is that it always predicts the FG to be a few points higher than the recipe I am copying.

I have tried changing the mash temps, changing the starter volume to no avail. Increasing the malt bill increases the OG but the FG stays the same. I have found that changing the efficiency does affect the FG. The efficiency I have set (72%) seems to always hit my volumes and the OG and even the FG. The problem is that I would like the predicted FG to match the recipe I am copying and be able to brew to hit the original lower FG than what my system projects.

So what do I need to change for Beersmith to predict the same FG as the copied recipe.

I hope this makes sense and am hoping for someone to show me the error of my ways.
 
You want to have your system dialed in with BeerSmith to match your actual OG and volumes.  You have indicated that it does this fairly well.  Your stated issue is that your fermentation achieves a higher attenuation than BeerSmith predicts.  Do I have that correct?

The first thing I would check is your thermometer calibration.  Make sure that what you read as 152F is in fact 152F and not 146F. 

Beyond that, you have a couple of options for adjusting the predicted fg through BeerSmith.  The first is to change the center point of the mash temp vs attenuation relationship which can be found in 'options' >> 'Advanced' > 'Center Mash Temp for FG adjust'.  Moving this number up (default if 153.5) will shift the fermentability of the wort (and therefore higher attenuation) to predict a lower FG.  This method will work the best if you use a variety of yeasts and find they all give you a lower

The second way is to adjust the attenuation range up for each yeast you use.  This will work the best if you consistently use a single yeast strain.
 
raysmithtx said:
So what do I need to change for Beersmith to predict the same FG as the copied recipe.

FG is influenced by the Max Attenuation of the yeast you choose. You'll find it in the yeast tab.

If all other things are lining up to match both the recipe and your brewery capabilities, then this is the correct adjustment.
 
Oginme said:
You want to have your system dialed in with BeerSmith to match your actual OG and volumes.  You have indicated that it does this fairly well.  Your stated issue is that your fermentation achieves a higher attenuation than BeerSmith predicts.  Do I have that correct?

The first thing I would check is your thermometer calibration.  Make sure that what you read as 152F is in fact 152F and not 146F. 

Beyond that, you have a couple of options for adjusting the predicted fg through BeerSmith.  The first is to change the center point of the mash temp vs attenuation relationship which can be found in 'options' >> 'Advanced' > 'Center Mash Temp for FG adjust'.  Moving this number up (default if 153.5) will shift the fermentability of the wort (and therefore higher attenuation) to predict a lower FG.  This method will work the best if you use a variety of yeasts and find they all give you a lower

The second way is to adjust the attenuation range up for each yeast you use.  This will work the best if you consistently use a single yeast strain.
I have double checked my thermometer and know it is correct. I think the yeast adjustment is a good place to start. I always use a yeast starter with a stir plate and aerate with pure oxygen. That may be why my attenuation is always below the predicted FG in Beersmith regardless of the yeast strain I use.

brewfun said:
FG is influenced by the Max Attenuation of the yeast you choose. You'll find it in the yeast tab.

If all other things are lining up to match both the recipe and your brewery capabilities, then this is the correct adjustment.
Thanks for taking the time to respond, That is where I will start.
 
Back
Top