Question about amounts of of sorbate

[hermon]

Hi Forum,
I'm a newcomer to this forum and I have some experience brewing (10 batches of LME, various types of ale.)

I've moved on to cider, as I have a friend who has a boutique winery and grows organic apples. We took some of his Grade B apples and pressed them into 300 liters of juice (!) and fermented them using a wine yeast. We've added sulfites to keep it fresh.

My plan is to neutralize the yeast using potassium sorbate, then to sweeten, and add CO2 artificially. My question is, how much sorbate will do the trick? I've seen some advice in this forum in terms of teaspoons per gallon, but I'd prefer to weigh the stuff before throwing it into my cider. What is the proper amount in grams per liter (it's OK if you send me ounces per gallon too, I can do the conversions despite the fact I'm located 6,000 miles away from the US!)
Thanks in advance

 

[CandleWineProject]

First off, sorbate doesn't kill yeast. It just keeps them from reproducing. So basically, you need your fermentation to be done before you add the sorbate to make sure it doesn't start back up. You aren't trying to stop it, just keep it stopped.

As for how much, that is usually on the packaging. Mine says 3/4 tsp per gallon. Sorry, I don't know what that is as a weight.

 

[hermon]

That's what I meant. Thank you for the clarification.
If there is not more exact amount, that's what I'll do.

I wonder if it is hygroscopic (absorbs moisture from the air.)