CJ wrote:
> I'm going to make a couple of batches of riesling this fall and I
> wanted to make one of these off-dry. I've made a lot of wine, but
> always fermented to dryness.
Been there, done that.
>
> I was wondering what is the best way to stop the fermentation once I
> get to the residual sugar level that I want ?
Cold.
>
> Is it simply a matter of adding enough sulphite to stop it (or sulphite
> and rack at the same time) ?
Definitely not guaranteed to work. At best, the SO2 will slow the yeast
down but you would have to add way more than you want to actually kill
the yeast.
>
> Will it be stable in this case, or could I end up just stunning the
> yeast only to have it start up again in the bottle ?
The latter is a very definite possibility.
>
> What about selecting a yeast that can only survive to 10 or 11 %alc
> (does this type of yeast exist commercially or can they all survive
> upwards of 12%) ?
According to a major wine yeast company, no such thing exists. At least
not one that will reliably stop around a certain ABV. It depends on too
many other conditions whether the yeast will stop at 16% or 12% or 8%.
>
> Do I need to filter it finely enough to remove all yeast (I'd prefer to
> avoid filtering if possible) ?
Pot. Sorbate in addition to the Pot. Meta. is another option.
>
> Any suggestions would be appreciated.
>
I've been looking into this for a few years since German style
Rieslings are a favorite of mine.
The best procedure I've been able to come up with is to chill the wine
almost to the freezing point right before you reach your target SG. I
say right before your target because the yeast will still consume sugar
while the wine is cooling down unless you have some method of really
quickly cooling it.
The cold will slow the yeast down to the point where they will become
inactive and settle out. The cold is not a reliable way to kill the
yeast, only temporarily inactive them. One the yeast have settled out
sufficiently, either filter or use sorbate.
The sorbate will prevent the remaining yeast from reproducing. Don't
use it without Pot. Meta. Riesling tends to be high in acid (including
malic) and MLF is not really in style plus can cause some off aromas if
sorbate is present. The Pot. Meta. will prevent the MLF.
Andy
|