Further questions regarding sorbate. How long will the inhibiting action last? Does it settle out and collect in the lees? Can a ferment be restarted after waiting a reasonable amount of time? After racking.
If sorbate has been added, and it is decided to get a higher abv, will adding sugar and a yeast starter do the trick?
This is strictly a hypothetical situation, you understand.
It is better if you start a new thread with your questions, but we will do it here since we are already here.
A reasonable amount of time??? That is very subjective. A month - it won't restart; a year - maybe, maybe not. After the sorbate has been present for 6 months, if one adds more yeast and some sugar, I'd bet it will start fermentation, but I can't say that for certain.
Sorbate works on the yeast that are present in the wine at the time it is added to the wine. Of course some of it can stay around for a longer time, even after several rackings. Some new yeast can always find their way into the wine at a later date.
I think the whole idea is to add the sorbate, then back sweeten immediately after. if you don't want to back sweeten right away, don't add the sorbate until you do.
Since sorbate doesn't kill the yeast, but only renders them unable to multiply, it works pretty fast. Even after racking the wine several times, I would not expect one normally would ever add more sugar and expect fermentation to get started again. That is the whole idea of adding sorbate, so the wine is protected when back sweetening.
However, again I have to ask what "is a reasonable amount of time"? If one waits a very long time, what I say will not be true. The effects of any such wine chemical will wear off eventually. To get specifics, this is a question one should ask the company that packages the sorbate.
