How much sugar to backsweeten a 6 gallon carboy?

[GeneseeEstates]

I am ready to bottle from a 6 gallon carboy of Moscato I ordered as a juice bucket I ordered from a club. After I fermented the wine, the finished gravity was 1.000, or just below. Wine has been in a carboy for a year and is ready to be bottled.

My question is where do I start for back sweetening? I was planning to rack off 750ml of the wine, and boil it with white sugar to make a syrup. Should I start with a half cup, one cup or 2 cups? How much sugar is a starting point?

I have never back sweetened wine. Yes, I have a fresh pack of potassium sorbate I’m ready to dose to prevent bottle bombs.

 

[BarrelMonkey]

If you're planning on making table wine (as opposed to much sweeter dessert wine) an appropriate range of sugar is in the 5-10g/L range (depending on acidity of your base wine; other things being equal, higher acidity wine can typically support higher sugar).

6 gal = 22.7L, so 10g/L is going to be 227g sugar, 5g/L will be half that.

Don't boil your wine! What I would do would be to make up a series of samples, maybe 100mL each and add proportional amounts of sugar to give, eg 5g/L, 7.5g/L and 10g/L (along with the non-adulterated base wine). Leave samples to integrate for a while (at least overnight) and then taste them. Blind tasting is the way to go here so that you're not biased by any preconceived notion of what the result should be.

When you've decided on your favorite balance of sugar, you can scale it up and add to the bulk wine along with the sorbate before bottling.

 

[Rice_Guy]

Howdy @GeneseeEstates , the answer to how much sugar is it depends on the Titratable acidity and tannin load. Are you part of Wisconsin Home Vinters? Last month I put something into the vinters press with a graphic of TA vs specific gravity for wines which have won ribbons in contest. As a cross check I will test sweetness above and below the theoretical target and have Mrs RiceGuy give feedback. Once I have picked the target I do a sugar calculation and may weigh sugar for individual bottles or may weigh sugar into a Pyrex measure > wet it with some wine (ex 1:1 by weight) > microwave till hot but not boiling over > stir to melt > let it dissolve fifteen minutes as is > microwave 20 seconds if not completely dissolved > then add.