Ask Wine Wizard

Sweetening Wine Without Refermentation


Craig Mason — St. Peters, Missouri asks,

I have done malolactic fermentation (MLF) on several wines and know that adding potassium sorbate to the wine can cause an incurable fault of geranium smelling wine. I have some wines that have gone through MLF and could benefit from being just a bit sweeter — one being an apple wine. I do not have the capability to sterile filter. Is there a way to make these sweeter and be assured that I won’t get refermentation?

Unfortunately, there are only so many options for preventing fermentation in sweet wines and they all involve some degree of sacrifice or difficulty. The list of “cons” is long compared with the one “pro” of an arrested fermentation. First off, you’re correct that adding sorbate can sometimes produce off-flavors over time. Secondly, fortifying with alcohol to a point high enough to retard refermentation (usually around 18% alcohol) is not ideal for all winemaking style goals; you’d be better off aiming to make a Port-style wine in the first place. Thirdly, it’s impossible to add enough sulfur dioxide to ward off fermen-tation without compromising aroma. Who wants to drink a wine that smells and tastes like sulfur dioxide? And finally, filtration is fiddly and, if you have to buy or rent the filter, can be expensive. So what’s a winemaker to do? Depending on the volume, and especially if you have access to a second fridge in your house or cellar, did you think about sweetening it and then chilling it? I’m thinking, especially if you saved it for a major
Response by Alison Crowe.