How do I fix a stuck fermentation?

Jun 26, 2018 11:36:13 AM Published in Wine Kits 1994 Views.

By definition, a stuck fermentation is a fermentation that has stopped before all the available sugar in the wine has been converted to alcohol and CO2. If the bubbles in your airlock slow down before your wine has reached terminal gravity (usually 1.000 or lower), you may have a stuck fermentation.

Here's how to check:

Is the specific gravity of your wine no longer falling, or tremendously sluggish? If you take hydrometer readings for three consecutive days, and the reading remains the same and is higher than 1.000, it’s probably stuck.  Is the temperature of your fermentation area between 65 and 75 °F? If it is too cold, the yeast can’t do it’s job (or does it very slowly). Fortunately, stuck fermentations are pretty rare. But when they do happen, it’s important to make corrections right away and get the fermentation going again for optimum results.

    Try the following tips to get that airlock bubbling again:

  1. Simply move the fermenter to an area that is room temperature, or 68-70 °F. In most cases, too low a temperature is the cause of a stuck fermentation, and bringing the temp up is enough to get it going again.
  2. Open up the fermenter, and rouse the yeast by stirring it with a sanitized spoon. Sometimes putting the yeast back in suspension will get it going again.
  3. If the above doesn't get the yeast going then Rack the wine off of the old yeast, and pitch some fresh yeast in, preferably a highly active strain such as Lavlin EC-1118.