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Campden Tablets Best Practices

TroubleShooting

Bryan Derry — Prosser, Washington asks,
Q

I’ve got a recipe that suggests I should crush and dissolve a Campden tablet and add it to the grape must (I’m planning on making a red wine from some spare Cabernet and Merlot I’ll be able to pick up from a friend this harvest) before fermentation. Won’t this kill off the yeast?

A
The great thing about Campden tablets (a convenient form of dosing in sulfur dioxide for home winemakers) is that they will inhibit the yeast and bacteria you do not want (which are sensitive to sulfur dioxide) while allowing the yeast you do want to continue to power through the fermentation. Longtime readers of my column know that I almost always inoculate my wines with a commercial yeast strain (purchased from a reputable dealer) that is specifically chosen for my wine’s conditions. Since you’re doing a red wine in the Prosser area, I’ll figure you’ll be able to get your grapes plenty ripe . . . and that you’ll need a yeast strain that can tolerate a temperature up to about 95 °F (35 °C) and an alcohol up to 15%. This will provide the best chance at a complete fermentation. One crushed Campden tablet in one gallon (3.8 L) of wine produces about 65 ppm (or mg/L) of total sulfur dioxide. A purchased yeast is grown and formulated to tolerate a little bit of sulfur dioxide and I almost always
Response by Alison Crowe.