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Recommended First SO2 Addition


Bob Joakimson — Concord, California asks,

How long do you wait before your first additions of SO2?

Thanks, Bob, for joining fellow columnists and me for our first ever virtual WineMaker Harvest Boot Camp this past September! This question didn’t get answered in my Q&A session held at the end of my “Top 5 Harvest Mistakes to Avoid” talk (there were a number of others that didn’t get answered either that I’ll try to get to in future columns) so, considering the depth of this question, I wanted to cover it here. SO2, otherwise known as sulfur dioxide, is added as an antioxidant and anti-microbial agent and has been used in winemaking since ancient times. Yeast cells even produce a small amount of sulfur dioxide themselves during the fermentation process, so in fact, there really is no such thing as a SO2-free wine, no matter how many folks touting “natural wine” or other kinds of vinous charlatanism would like us to believe otherwise.So back to the question of when it’s opportune to first add sulfite to wine: I almost always add a little bit, say around 25 ppm total, at the crusher or juice stage for reds,
Response by Alison Crowe.