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.

 

[Hokapsig]

Download the Fermcalc app onto your computer or cell phone.

bench test Specific Gravity in 50 cc batches in increments of 0.01, 0.02, etc. Then when you like 2 ranges, you can then narrow down the range in 0.005 increments and so on until you get to the desired SG

 

[winemaker81]

My advice is to completely ignore the numbers. No spreadsheet, calculator, or meter will drink your wine. Backsweeten to taste. Trust your senses.

I've tried the "backsweeten a small quantity, then scale the sugar to the full batch" and had a couple of dismal failures. In theory this should work perfectly. In practice? Mother Nature and Dionysus like to mess with us. Or maybe I did the calculations wrong. Either way, the resulting wine was too sweet for my taste.

Where to start? Since you don't normally backsweeten, start with 1/4 cup sugar in 19-23 liters. Use a drill-mounted stirring rod and pour in table sugar in a thin stream while stirring. Stir for 30 second after adding the sugar.

Taste it. It's best to have at least one other person present, to provide a contrasting opinion.

Repeat in 1/4 cup increments until you think it needs just a bit more. STOP. It doesn't. Trust me on this point. As I often say, "it's easier to add more than to take some out."

Last month my elder son and I constructed a "Port". You may find that description useful.

 

[Raptor99]

My advice is to completely ignore the numbers. No spreadsheet, calculator, or meter will drink your wine. Backsweeten to taste. Trust your senses.

I agree. Any numbers that you come up with are merely a starting point. The amount of sugar needed to achieve the right balance is dependent on the acidity, amount of tannins, ABV, and the type and variety of fruit. There is no one size fits all answer. Add the right amount of sweetness to make the wine that you want to drink. You can do bench testing with some samples and/or add a little bit at a time until it seems almost sweet enough.

I measure how much sugar I add per gallon (I use simple syrup), and record that in my notes. That gives me a good estimate of what I will need the next time I make that type of wine using the same recipe.

Keep in mind that as it ages the character of the wine will change. As the tannins soften, it might require a little less sugar to taste right than at the time you bottle it. That is one benefit of doing some bulk aging for 6+ months before you bottle.