OG and adding sugar into fermenter

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I brewed up a nice big Barleywine two months ago (it's sitting in secondary until October) and I used some corn sugar additions in the fermenter because I read that it is better to add them on the back end of fermentation rather than at the start. This will of course produce more alcohol and a lower FG, but my question is in relation to the OG.

When someone asks what my OG was for this barelywine what number do I use? The OG I obtained going into the fermenter (1.115) with the caveat that I added sugar to increase abv and lower FG? Or the number that beersmith predicts (1.125) even though it is assuming I added the sugar into the kettle before fermenting.

I also assume I would use the 1.125 value for calculating abv, correct?
 
Use the gravity as if you added to the kettle and you'll get the right numbers for OG and ABV.
Adding sugar won't lower your FG, though, it just is fully fermentable and won't leave any residual unfermented sugars like malt will.
 
Use the gravity as if you added to the kettle and you'll get the right numbers for OG and ABV.
Adding sugar won't lower your FG, though, it just is fully fermentable and won't leave any residual unfermented sugars like malt will.

Isn't the hydrometer affected by the amount of alcohol in solution? The more alcohol the lower it will show? I thought that's why the refractometers don't work without a correction factor for FG? Alcohol is less dense than water is it it not, so it would stand to reason that if other volume was the same if I added more alcohol (via sugar fermenting) it should reflect a lower FG?
 
An all malt beer made with 11 pounds of malt and 1.060 OG will end up around 1.015.
A beer made with 11 pounds of malt and 2 pounds of sugar for a 1.078 OG will end up around 1.015 also.
No lower gravity, but perhaps the perception it is drier because there is more alcohol present.
 
Isn't the hydrometer affected by the amount of alcohol in solution? The more alcohol the lower it will show? I thought that's why the refractometers don't work without a correction factor for FG? Alcohol is less dense than water is it it not, so it would stand to reason that if other volume was the same if I added more alcohol (via sugar fermenting) it should reflect a lower FG?
You will effectively replace a bit of water per volume with alcohol by adding sugar. This will lower the overall gravity as alcohol has a lower gravity than water on it's own.

Refractometer do not work with gravity but with the angle, light is reflected with, on the solution. The angle is then displayed on a scale which shows the resulting gravity. Add the angle might be changed by the alcohol, as well as sugar, a correction might be necessary.

I think that sugar, using a hydrometer, might indeed lower fg readings without actually removing unfermentables. Maybe it is just such a low error that it doesn't really matter.
 
An all malt beer made with 11 pounds of malt and 1.060 OG will end up around 1.015.
A beer made with 11 pounds of malt and 2 pounds of sugar for a 1.078 OG will end up around 1.015 also.
No lower gravity, but perhaps the perception it is drier because there is more alcohol present.

That doesn't make sense to me. If there is more alcohol in the solution the density will be less and thus the hydrometer should sit lower in the solution.

It could be as the poster above mentioned that the actual difference between where the hydrometer is sitting is so small as to be negligible or within the margin of error for our sight on the hydrometer. Or perhaps the difference is simply overpowered by the residual sugars that remain so it again doesn't show the difference. That would explain it.

But you seem to be implying that if I took a volume of water and measured it at 1.000 and the same volume of a solution of water and alcohol it would still measure 1.000. That doesn't make sense to me. The solution in the example should be less than 1.000
 
That doesn't make sense to me. If there is more alcohol in the solution the density will be less and thus the hydrometer should sit lower in the solution.

It could be as the poster above mentioned that the actual difference between where the hydrometer is sitting is so small as to be negligible or within the margin of error for our sight on the hydrometer. Or perhaps the difference is simply overpowered by the residual sugars that remain so it again doesn't show the difference. That would explain it.

But you seem to be implying that if I took a volume of water and measured it at 1.000 and the same volume of a solution of water and alcohol it would still measure 1.000. That doesn't make sense to me. The solution in the example should be less than 1.000
That is correct.you can look up the varying gravities of different percentages of alcohol solved in water online. They are below 1.

This is the reason why cider can get as dry as gravity below 1 sometimes, when the sugar is fully fermented.
 
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Hydrometer measures density of the liquid due to presence of sugars. Nothing to due with alcohol.
 
Well it's true
What you wrote? Sorry but no.

Alcohol lowers gravity of the liquid, sugar raises gravity of the liquid. The more alcohol the heavier the impact and the same regarding the sugar.

The specific gravity is the result from everything solved and floating in the liquid, including the two above. The hydrometer does not specifically show sugar, it does show gravity. Therefore the more alcohol, the lower the gravity which can give you a false idea about the amount of residual sugars.
 
What you wrote? Sorry but no.

Alcohol lowers gravity of the liquid, sugar raises gravity of the liquid. The more alcohol the heavier the impact and the same regarding the sugar.

The specific gravity is the result from everything solved and floating in the liquid, including the two above. The hydrometer does not specifically show sugar, it does show gravity. Therefore the more alcohol, the lower the gravity which can give you a false idea about the amount of residual sugars.
I think we're saying the same thing. If alcohol becomes present it's because there is less sugar now present and vice-a-versa.

What made me speak up was that OP was implying that the hydrometer reading was affected by alcohol, meaning you have to make an adjustment ala using a refractometer, which isn't true.
 
I think we're saying the same thing. If alcohol becomes present it's because there is less sugar now present and vice-a-versa.

What made me speak up was that OP was implying that the hydrometer reading was affected by alcohol, meaning you have to make an adjustment ala using a refractometer, which isn't true.

I think you misunderstood my points. I know there is no correction factor needed for Hydrometers like there is for refractometers. Another poster was implying that the alcohol has no effect on the hydrometer. I'm simply saying it does by lowering the gravity of the liquid.

If I add 15 pounds of sugar to my beer, it's going to have a lower gravity measured by the hydrometer than if I don't. The previous poster was stating differently.
 
OP was implying that the hydrometer reading was affected by alcohol

It is, thats just physics. Add pure alcohol to water and you will end up with a gravity of below 1.0. Therefore if you add just alcohol (say from just adding a fully fermentable sugar) it will indeed lower the overall gravity of the sample in question. Its just a small enough amount (at the amount we might be using anyway) that its not enough to really worry about.
 
It is, thats just physics. Add pure alcohol to water and you will end up with a gravity of below 1.0. Therefore if you add just alcohol (say from just adding a fully fermentable sugar) it will indeed lower the overall gravity of the sample in question. Its just a small enough amount (at the amount we might be using anyway) that its not enough to really worry about.
I think what we forgot is that we do not look at the fg only, but also at the OG and the OG does include the additional sugar (at least when done correctly). Those formulars which then calculate the alcohol amount based on the difference of those two, do take the gravity lowering effect of alcohol into account.
 
Isn't the hydrometer affected by the amount of alcohol in solution? The more alcohol the lower it will show? I thought that's why the refractometers don't work without a correction factor for FG? Alcohol is less dense than water is it it not, so it would stand to reason that if other volume was the same if I added more alcohol (via sugar fermenting) it should reflect a lower FG?

An all malt beer made with 11 pounds of malt and 1.060 OG will end up around 1.015.
A beer made with 11 pounds of malt and 2 pounds of sugar for a 1.078 OG will end up around 1.015 also.
No lower gravity, but perhaps the perception it is drier because there is more alcohol present.

Hydrometer measures density of the liquid due to presence of sugars. Nothing to due with alcohol.

If you have a beer that has unfermentable sugars in it and an FG of, say, 1.015. You then add a fully fermentable sugar to it, that sugar will ferment out. It will increase the "combined" OG, increase the alcohol content. But, it will still finish with a gravity of 1.015.
 
You guys are going to make me go buy a new hydrometer and brew up some beer to show you...
 
It is, thats just physics. Add pure alcohol to water and you will end up with a gravity of below 1.0. Therefore if you add just alcohol (say from just adding a fully fermentable sugar) it will indeed lower the overall gravity of the sample in question. Its just a small enough amount (at the amount we might be using anyway) that its not enough to really worry about.

But you aren't adding alcohol to water. If you add a fully fermentable sugar to a 1.015 wort and it ferments out. You will still have a wort with enough unfermentable sugar to end up at 1.015. If it somehow enables the yeast to ferment some of those long chain sugars it might drop to 1.014 or so. But the added sugar didn't make the difference.

The hydrometer is just measuring the density. Unless you are adding a liquid alcohol then it is also changing the volume, diluting the sample.
 
But you aren't adding alcohol to water. If you add a fully fermentable sugar to a 1.015 wort and it ferments out. You will still have a wort with enough unfermentable sugar to end up at 1.015. If it somehow enables the yeast to ferment some of those long chain sugars it might drop to 1.014 or so. But the added sugar didn't make the difference.

The hydrometer is just measuring the density. Unless you are adding a liquid alcohol then it is also changing the volume, diluting the sample.

The density of alcohol is lower than the density of sugar. So you're adding sugar, that you will measure as such when you take your OG. But then that same sugar ferments out completely, leaving you with more of the less dense alcohol and none of the more dense sugar. That would lower the the density of the liquid of the end product when you take your FG, thus a lower measured FG. You hit the nail on the head with your dilution comment, as by adding fully fermentable sugar to your starting product effectively dilutes the final product with more alcohol.
 
The density of ethanol is lower than the density of water or a sugar solution. Ethanol SG is 0.785. I was not saying there would be no difference, but that it is negligible. A 5% solution of ethanol and water would be 0.98925 and a 10% solution of ethanol and water would be 0.9785. I doubt most can visually discriminate the difference of 0.01075 in gravity with their hydrometer. Add sugar/dextrins/proteins, etc. making up the density of the solution and I doubt a homebrewer would be able to measure a significant difference.
 
The density of ethanol is lower than the density of water or a sugar solution. Ethanol SG is 0.785. I was not saying there would be no difference, but that it is negligible. A 5% solution of ethanol and water would be 0.98925 and a 10% solution of ethanol and water would be 0.9785. I doubt most can visually discriminate the difference of 0.01075 in gravity with their hydrometer. Add sugar/dextrins/proteins, etc. making up the density of the solution and I doubt a homebrewer would be able to measure a significant difference.

And that's fine. That makes sense to me. Your other post just confused me because it implied there was no difference. There IS a difference. It's just not reliably detectable with the sensitivity of our equipment and margin of error.

Which also makes sense why it's easier to add it to the og side rather than then relying on the fg side, even if you're not adding it at a time where it would affect your actual og measurement.
 
The density of ethanol is lower than the density of water or a sugar solution. Ethanol SG is 0.785. I was not saying there would be no difference, but that it is negligible. A 5% solution of ethanol and water would be 0.98925 and a 10% solution of ethanol and water would be 0.9785. I doubt most can visually discriminate the difference of 0.01075 in gravity with their hydrometer. Add sugar/dextrins/proteins, etc. making up the density of the solution and I doubt a homebrewer would be able to measure a significant difference.
Well a wide range hydrometer can measure a difference of about 0.001 - 0.0015 in SG, and a narrow range one can measure a difference of about 0.0005. So, yes we can easily discriminate a difference of 0.010. That's the same difference as 1.040 to 1.050. We do that all the time.

Brew on :mug:
 

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