Predicting OG and FG when using Table Sugar

THops

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I've been brewing Belgians and adding table sugar to create dry beers and up the ABV. Or increase "digestibility" as the Belgians say! Works like a charm.

The one thing that always throws me, though, is that sugar seems to really enhance attenuation. I'm trying to figure out HOW much it accelerates attenuation, because I keep missing my FG numbers.

My recipes in Brewer's Friend will predict an FG of say, 1.012, but my beers keep finishing at 1.003. They taste great, and more ABV is fine, but we all know how great it is to hit your numbers. And understand how to predict them.

Adding a pound of sugar to a 6 gallon batch ups my OG around 8 or 9 points I've found. Interestingly, it also seems like my calculations in Brewer's Friend miss the FG by about the same amount when I use sugar.

Is it too easy to predict that whatever gravity points get added by the sugar, they take away approximately the same points when calculating FG? Since sugar is 100% fermentable?

So, while Brewer's Friend may predict an FG of 1.012, I should reduce that prediction by the same amount of gravity the sugar added?

I know what I CAN do is adjust the attenuation prediction in the recipe. If I put in a custom 95% attenuation, I can get a lot closer to the actual FG's I'm getting.

But is there some rule of thumb to predict how various sugars can impact FG's? The Brewer's Friend Recipe calculator does not seem to automatically take that into account...
 
Is it possible that I just over-pitched?
No. Overpitching does not cause increased attenuation, often it may have the opposite effect. The thing with sugar is that all the sugar ferments to alcohol and carbon dioxide, the co2 goes away and what's left is alcohol, which is way lighter than water. This will cause an increased drop in the overall gravity because it's so light in weight, which can seem disproportional on the surface.

The calculator is there to give an estimate of final gravity, but it should not be relied on for accuracy. The mash, the grist, the yeast and the health of the fermentation all play a hand in the final gravity. Keep notes, especially in regards to yeast and grist make up. Each strain of yeast have different characteristics as far as the attenuation. Some can chew through anything it seems, others don't. Sugar can short cut a recipe that has a lot of unfermentables, dropping the gravity lower than had sugar not been added. It's kind of weird, higher OG, but lower FG.

You have a good problem in my opinion. Great attenuation which equates to healthy fermentations.
 
If you were using malt and not just sugar that is suspiciously low, but your recipe is private so not sure.
 
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Thanks, yeah, it's a good problem to have overall. But not if I want to enter a beer in a competition... I was shooting for 7.5% ABV, but I'm at 9%. I'm outside of the style range.

Of course, brewing is about experimenting and learning. For this recipe next time, my plan is to Mash really high and cut the sugar in half. That should give me some more data points...
 
If you were using malt and not just sugar that is suspiciously low, but your recipe is private so not sure.

Sorry, wasn't sure if I could just post the link. The recipe is open now. I appreciate your help!
 
I see it now. 1.000 is rather sus as the kids say for that much malt. You seriously threw 3 different yeasts in the fermenter?

How does it taste?
 
Yeah, been using 3 yeasts and it works great. I submitted my previous beer in my first competition and it won first place! It was a saison and it used three yeasts. That one also fermented down to 1.000/1.0002.

The one in the fermenter was supposed to be a Belgian Blonde, and I needed the FG to at least stay above 1.008 for the style. It's now really a Tripel, though the IBU's are a bit low for that style. It should still hopefully be a tasty beer!
 
Thanks, yeah, it's a good problem to have overall. But not if I want to enter a beer in a competition... I was shooting for 7.5% ABV, but I'm at 9%. I'm outside of the style range.
Don't get too hung up on the stats when entering a competition. A friend of mine gave me great advice years ago. "Don't enter the beer you brewed, enter the beer you ended up with". Sometimes a Helles tastes like a Kolsch, Or a Pale ale tastes like an IPA. Or a Saison ends up as a great Tripel. One trick to do is to enter the same beer in multiple categories. For instance, I just brewed a Dunkel recently, it taste to me like an Oktoberfest. So why not enter it as both? I have entered the same beer in comp, taking first and second place with the exact same beer. I have done that multiple times and the judges weren't the wiser I had done that.

If the beer turned out great, enter it in the category that best suits the beer you ended up with. Stategery!
 
That's wild it finishes that low but if you consistently get that and they're good then nothing to worry about.

I entered the same beer in 3 different competitions and got wildly different scores so I don't worry to much about it.
 
Don't get too hung up on the stats when entering a competition. A friend of mine gave me great advice years ago. "Don't enter the beer you brewed, enter the beer you ended up with". Sometimes a Helles tastes like a Kolsch, Or a Pale ale tastes like an IPA. Or a Saison ends up as a great Tripel. One trick to do is to enter the same beer in multiple categories. For instance, I just brewed a Dunkel recently, it taste to me like an Oktoberfest. So why not enter it as both? I have entered the same beer in comp, taking first and second place with the exact same beer. I have done that multiple times and the judges weren't the wiser I had done that.

If the beer turned out great, enter it in the category that best suits the beer you ended up with. Stategery!

Ha! Yeah, my Blonde is now a Tripel, which is a good "problem" to have. Still, I want to improve my skills and knowledge, and this mystery is a bit perplexing. I can of course keep brewing it over and over, and I bet I will figure it out.
 
Ha! Yeah, my Blonde is now a Tripel, which is a good "problem" to have. Still, I want to improve my skills and knowledge, and this mystery is a bit perplexing. I can of course keep brewing it over and over, and I bet I will figure it out.
If you keep at it, the sugar additions and everything that goes with it will become second nature. Congrats on your win! Be careful though, it can become addictive.
 
So another theory, for what it's worth...

I think I started going with a 90 minute mash at the same time I started getting these high attenuations and low FGs. Could it be that I am simply making a too fermentable wort?

I mashed at 154 for the current beer, which I felt was on the high side for a Belgian, but I still ended with 1.000 FG.

I wonder what would be the most effective in raising the FG's a few points?

1. Mash a lot higher. Maybe try 160?

2. Mash for a shorter time. 45 minutes?

3. Use less sugar (this one seems obvious, but if everything keeps fermenting out, maybe not).

4. Start with more grain/higher OG (again, seems obvious, but not if it ferments out).

I really don't want to keep hitting 1.000 by accident. I'd rather be able to control my process better....
 
I'd bet it's one of your yeasts personally, maybe a diastatic one?

I'd suggest do a simple SMaSH (single malt single hop) beer for an hour at 152, then pitch one pack of something like US-05 or BRY-97 in.

Then see where it finishes. If you still finish at 1.000 then something is very odd and you probably have an infection.

Standard SCIENCE! things, reduce as many variables as possible and then start adding them back in.

I like Marris Otter and Fuggle for a nice simple Englishish beer.
 
I'd bet it's one of your yeasts personally, maybe a diastatic one?

I'd suggest do a simple SMaSH (single malt single hop) beer for an hour at 152, then pitch one pack of something like US-05 or BRY-97 in.

Then see where it finishes. If you still finish at 1.000 then something is very odd and you probably have an infection.

Standard SCIENCE! things, reduce as many variables as possible and then start adding them back in.

I like Marris Otter and Fuggle for a nice simple Englishish beer.

Sound advice, to be sure. It's just that every brew day is precious (I can only brew about once a month), so not sure I'd want to use one that way, if I am being honest. But I do think I will have to solve this through experiments, for sure!

My current plan is to mash my next beer higher and cut the sugar. Thinking Belgian Pale, so I actually don't even need the sugar...

If I do have an infection, it must be a GOOD one!
 
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Sugar increases attenuation, so cut back on that. My newbie opinion :)
 

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