Troubleshooting Sluggish and Stuck Fermentations—Can you Get Back on Track without a Restart? There are several factors that affect the success of fermentation, and sometimes a small adjustment can get things back on track without the need for a full restart. Below we outline some common causes of problematic fermentations and advice for next steps. TEMPERATURE STRESS   Each yeast strain has an optimal temperature range and anything outside of this range can cause yeast stress. If the temperature was too high or spiked, the yeast may not be viable and a restart may be needed. If it is too low, try slowly warming the wine to 70°F.   INADEQUATE MIXING If the tank isn’t mixed, yeast may settle and lose access to nutrients and sugar. This can slow fermentation or cause it to stall. Gentle mixing during fermentation helps keep yeast active and fermentation on track.  WINE MIGHT NEED DETOXIFICATION When yeast become stressed, they can produce compounds th