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Fermentation Troubles


Lauren Mowery — New York, New York asks,

What are the most common fermentation problems you encounter in your own cellar as well as in the “Wine Wizard” column?

Hi Lauren, great question. There are so many steps along the way where a fermentation can get into trouble, or “go pear shaped” as my interns from New Zealand used to say. We could almost do a walk through from start to finish, or even picking to dryness and say well, it could go south on you at this point, here, here, and here . . . but then we might get discouraged and never make wine again. For home winemakers, I think there are two common fermentation problems that tend to crop up the most: Proper yeast nutrition and fermentation temperature control. It’s relatively easy to measure the “big numbers” like Brix (sugar content/soluble solids by density) and even pH and total acidity. Those are all pretty inexpensive analyses to do for any home hobbyist who wants to do a little wet chemistry and play mad scientist in their own little home lab. The harder analyses to do are those like amino acid analysis and nitrogen content for nutrition, for which commercial wineries or wine labs spend thousands of
Response by Alison Crowe.