First time making a wine; sulfite and/or sorbate when sweetening?

[GlowingApple]

I've made some meads and ciders before, but I'm making my first fruit wine. Got several pounds of concord grapes from some friends in Erie, PA. I have about 1.5 gallons, split into a 1-gallon jug and a growler, both with airlocks, and I'm thinking of sweetening 1/2 gallon.

I've added potassium sulfite to each jug when I racked them the first time after fermentation stopped, and added more when I racked again after ~3 weeks (once the lees had settled). The wine is looking very clear now, but I'm thinking I'll probably wait about another month to let any more sediment fall out and then bottle. Or should I wait longer?

A couple days before I bottle I assume it would be best to add sulfite again? For the 1/2 gallon (that I want to sweeten) I'm not sure if sulfite alone is enough, or should I add potassium sorbate also? I'll let that jug sit for a couple weeks more just to make sure fermentation doesn't restart.

Thanks!

 

[Yooper]

If you are sweetening, you must add sorbate.

Sulfites are used as antioxidants, generally in the amount of 50 ppm or so. I guestimate that as 1 "dose" of 1/4 teaspoon of the powder or 1 crushed campden tablet per gallon, at every other racking and at bottling. If you've added it at that interval, then you'd add it at bottling but it sounds like it's already been added more than enough.

Remember to not bottle until no more lees fall in a fresh carboy for at least 60 days- then you can rack onto the sorbate solution (and sulfite if using). Let that sit a few days, then sweeten to taste and let that sit a few days. If the wine stays clear, no further fermentation starts, and no lees fall, it can be bottled.