Final Gravity Question

[Black Clover]

So, I don't know if this has been answered on the forum yet, but I was curious about final gravity and the mash schedule used in the recipe editor. I have been playing around with BeerSmith for a while, and I've noticed that the final gravity of your recipe changes depending on the mash schedule used. My question is, is there something similar in Brewer's Friend because I've pretty much matched up my recipes in both programs, and Brewer's Friend doesn't adjust FG for mash schedules.

(If this has been talked about previously, please direct me to that thread, and I will get to reading. Thank you.)

 

[Sunfire96]

The recipe calculator doesn't. I've seen the mods claim that mash temperature and schedule doesn't affect final gravity, but there's a lot of literature that shows both sides to the argument.

 

[Black Clover]

It doesn't. I've seen the mods claim that mash temperature and schedule doesn't affect final gravity, but there's a lot of literature that shows both sides to the argument.

That's what I was seeing too. I know there's formulas to calculate it and literature, but maybe it could be a potential feature in the future.

 

[Minbari]

In reality it does. temp will effect it the most. lower temp is more fermentable. thus, will have a lower fg

 

[Sunfire96]

I also wish the OG/FG would change when manually entering water amounts. If the calculator predicts I'll need 6.2 total gallons, I want it to tell me what the OG would be if I used 6 instead

 

[Black Clover]

I also wish the OG/FG would change when manually entering water amounts. If the calculator predicts I'll need 6.2 total gallons, I want it to tell me what the OG would be if I used 6 instead

That would also be nice, because some of the water calculations are to specific and I need to round up or down, depending.

 

[Mont Y. Märzen]

I thought it did. (or used to) However, I noticed that and other things in the editor are a bit buggy on updating live. I sometimes have to manually re-save it after such edits, or even exit and re-open the recipe for editing to see the effect of the change. But it's been a few moons since I've worked on a recipe.

 

[Mont Y. Märzen]

The recipe calculator doesn't. I've seen the mods claim that mash temperature and schedule doesn't affect final gravity, but there's a lot of literature that shows both sides to the argument.

In the meantime, I do Fast Ferment Tests (FFTs) with the residue in my starter flask on a stir plate at warm temps using my OG sample. That tells me what to expect for that yeast on that wort made from that mash temp, schedule and time. I then use that apparent attenuation to adjust the recipe accordingly. This is more real-world accurate than formulas built with assumptions and equipment dependent best-fit curves anyway.

If you don't have a stir plate, just use a sanitized mason jar and shake it a few times a day. An FFT takes about 2–4 days at room temp or warmer, long before primary is complete so you'll know what to expect. (unless you're using a beast like Kveik!) If you don't make starters, save a few specs from your dry pouch to your FFT, or squeeze a dribble out of your liquid pouch. No airlock needed—a sanitized foil cap works fine. (so their are no accidental bugs that might alter fermentation)

 

[Black Clover]

In the meantime, I do Fast Ferment Tests (FFTs) with the residue in my starter flask on a stir plate at warm temps using my OG sample. That tells me what to expect for that yeast on that wort made from that mash temp, schedule and time. I then use that apparent attenuation to adjust the recipe accordingly. This is more real-world accurate than formulas built with assumptions and equipment dependent best-fit curves anyway.

If you don't have a stir plate, just use a sanitized mason jar and shake it a few times a day. An FFT takes about 2–4 days at room temp or warmer, long before primary is complete so you'll know what to expect. (unless you're using a beast like Kveik!) If you don't make starters, save a few specs from your dry pouch to your FFT, or squeeze a dribble out of your liquid pouch. No airlock needed—a sanitized foil cap works fine. (so their are no accidental bugs that might alter fermentation)

I like this idea. Have you tried it with lager yeast or cooler temp yeast strains?

 

[Mont Y. Märzen]

It works for any strain. The FFT is always done 'hot' regardless. The reason for fermenting some strains cooler is to reduce off flavors/aromas. Your not going to drink the FFT, it's just a test of attenuation for that specific batch. Also, those cooler fermentations slow down the yeast. This is a Fast Ferment Test—you want it to finish before the main batch so you have an idea in advance where it will end up. This helps determine if the batch has stalled out, or if it indeed is done.

Another way to confirm a batch is finished fermenting is to take a pH of your OG sample before the FFT, then compare that to the pH of samples from the main batch as you arrive at your expected FG. Even if gravity stalls out where you expect, if the pH is still dropping, the yeast are still working. Wait until BOTH gravity and pH stabilize before racking out of the fermenter.

 

[Black Clover]

It works for any strain. The FFT is always done 'hot' regardless. The reason for fermenting some strains cooler is to reduce off flavors/aromas. Your not going to drink the FFT, it's just a test of attenuation for that specific batch. Also, those cooler fermentations slow down the yeast. This is a Fast Ferment Test—you want it to finish before the main batch so you have an idea in advance where it will end up. This helps determine if the batch has stalled out, or if it indeed is done.

Another way to confirm a batch is finished fermenting is to take a pH of your OG sample before the FFT, then compare that to the pH of samples from the main batch as you arrive at your expected FG. Even if gravity stalls out where you expect, if the pH is still dropping, the yeast are still working. Wait until BOTH gravity and pH stabilize before racking out of the fermenter.

Ah, okay. I'm starting to see what you mean. It's just a test of attenuation of the yeast. So, the FFT temp is not a big concern.

I'm starting to like this FFT more and more. I will give it a shot on my next batch.

 

[Mont Y. Märzen]

There is also a specific Log Entry in the Brew Session for an FFT.