Adding sugar --- "dry" out a beer?

[bwarbiany]

Over on beeradvocate, one of the members is asking whether adding sugar will help to "dry" out his beer. I.e. if he had a beer that finishes at, say, 1.018 when it should be 1.014 or so, and tastes too sweet, will adding sugar-- which will lower his FG-- make the beer taste more "dry".

For me, I said no. I think sweetness is a function of residual sugars, and adding sugar will reduce your OG (and add alcohol) without actually reducing those residual sugars. But I'm not sure of that answer.

Any thoughts?

[brahn]

I don't think adding sugar will actually lower the FG. The FG should remain the same, but it would make it seem like the OG was higher. It's possible that it would wake the yeast up and make them consume more of the sugar already in the wort, but I don't think that's likely if the beer has already finished fermenting. That said, I don't think it will dry out the beer, though it will add alcohol which might help the beer seem more balanced if it's too sweet.

[bwarbiany]

Brent,

Most sugar (at least the stuff we'd been discussing in that thread) is 100% fermentable. So every bit of sugar turns to alcohol. Alcohol has a specific gravity of something in the range of 0.79, water has a specific gravity of 1.000. So adding more alcohol (without adding unfermentable sugar) will actually reduce the FG.

Hence why some beers can finish with an FG below 1.000, despite the fact that there is still unfermentables in the beer.

[backyard brewer]

I don't think it'll dry out the beer because of the presence of the unfermentables that got him there in the first place. It might make it taste a little lighter, but not dry it out. If I were in this situation and just couldn't live with the higher gravity beer for some reason.... I'd experiment with Beano. A drop to start with and another each day until such time as I got the gravity down the couple points I was trying for.

But in real life I'd just enjoy the beer and try a lower mash temp next time.

[jward]

I guess if you ask will the beer have a lower FG you answered the question with a yes showing how adding alcohol reduces the FG because alcohol has a lower SG. Does that make the beer more "dry"? Did you run any numbers to see how much alcohol is need to reduce the FG? I agree that it will still taste sweet. Spike a beer sample with some vodka and see if tastes dryer or has the same sweetness.

I'd like to hear what Pete says about this. I think he blends wines and meads to improve each when they are too sweet/dry/whatever.

[brahn]

Brad, I almost edited my post to say that it won't significantly change the FG. I think you'd have to add a lot of sugar to make any noticeable change in the FG but I haven't done the calculations. Either way, you're still left with all the unfermentables and the body/sweetness that they bring.[/b]

[Oskaar]

Adding sugar will indeed increase the alcohol level if your yeast are robust enough to ferment it completely. Most of the yeast I use will take every bit of fermentable sugar to complete fermentation. Alcohol is perceived as sweet by the human tongue. If there is indeed extract (non-soluable-solids and unfermentable sugars) left in the beer the lower ending gravity will certainly lend to an overal "drier body" but the perception of sweetness may be increased as well. This is a very common state in wines that have been aged sur-lie (on the lees), barrel aged (due to the infusion of wood sugars, vanillin,lignin, furfurals, etc.) and late harvest fruit with high sugar content. Bear in mind most of my starting gravities are at or above 1.130.

Case in point, I routinely ferment my dry meads below .999 and well on down to .992. While this is bone dry on the scale of gravity, the perception of the honey character is increased and registered by most people who taste it as sweet, even when bone dry. I've found this to be the same in my experiences with beer when there are residual unfermentable sugars, barrel aging, lees aging, etc. Also bear in mind that as your yeast approach alcohol toxicity, many of the new buds will not come full term to maturity and will lyse prematurely. By adding sugar during the ferment this will change the osmotic pressure of the fermenting wort and in many cases will cause your yeast to stress and give off a sulfury character. This is different than autolysis because your yeast are being exposed to a toxic environment prior to the normal progression of the death phase. Another factor to consider is that as yeast cells lyse they release their oganelle and impart a sweet flavor. I haven't exprimented with this extensively with beer, but I have with wine and mead. Any of you who tasted my dry mead can attest that the honey character and perceived sweetness were very apparent in the character even though the gravity of that mead was 0.994.

Hope that helps,

Oskaar