I'm going to be using potassium sorbate and sodium metabisulphite, which I was hoping would prevent risk refermentation.
Please read this it explains it far better than i could -
How To Stop A Fermentation
By Ed Kraus
Using Potassium Sorbate
Potassium Sorbate is another home wine making ingredient that many winemakers consider when trying to stop a wine from fermenting any further. There is a lot of misunderstanding surrounding this product.
It is typically called for by
home wine making books when sweetening a wine. This is a situation where the fermentation has already completed and is ready for bottling. You simply add the Potassium Sorbate along with the sugar that is added for sweetening.
The Potassium Sorbate stops the wine yeast from fermenting the newly added sugar. So, many winemakers assume Potassium Sorbate can stop an active fermentation as well. But, nothing could be further from the truth.
Potassium Sorbate does not kill the yeast at all, but rather it makes the wine yeast sterile. In other words, it impairs the wine yeast's ability to reproduce itself. But, it does not hinder the wine yeast's ability to ferment sugar into alcohol.
Potassium Sorbate puts a coating on the cell wall of each individual wine yeast in such a way that budding or multiplying is next to impossible.
The idea here is that if you happen to have few cells of live wine yeast remaining in your finished wine, they will be rendered harmless if they are unable to regenerate themselves to great enough numbers to invigorate a fermentation of any kind. This is true even if more sugar is added to the finished wine.
Using Sodium Bisulfite or Campden Tablets
Many winemakers will turn to sulfites such as that found in
Sodium Bisulfite or
Campden Tablets for the answer. But, these two items are not capable of reliably killing enough of the wine yeast to guarantee a complete stop of the activity--at least not at normal doses that leave the wine still drinkable.
Once the bulk of the sulfites from either of these
home wine making ingredients dissipate from the wine into the air--as sulfites do--there is a very strong chance that the remaining few live wine yeast cells will start multiplying and fermenting again if given enough time. And, I might add that this usually happens at a most inconvenient time, like after the wine has been bottled and stowed away.