Stuck fermentation Stuck fermentation occurs when your beer fails to ferment to completion. This can result from the use of old yeast or poor ingredients. The best way to take care of this problem, is to prevent it from starting. To do this, you should: 1. Re-hydrate the yeast by adding it to some water and adding wort to the yeast an hour or more before you pitch. This will help ensure that your yeast is still active. 2. Use an all malt or a recipe that has a lot of it, as yeast needs nutrients to stay alive. Corn and sugar lack these nutrients. If your yeast still fails to survive, it cannot reproduce. For this very reason, distilled water shouldn’t be used when making beer.
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