My Fermentation Has Too Much Sugar. What Should I Do?

Stuck FermentationOh OH, Mr.” wineproblemsolver”,I have a stuck ferment in my wild grape wine at 1.012. I tried adding a fresh yeast culture and yeast nutrient and it has not responded. My guess is I had the sugar to high. I was reading about 1.090 at the start but realized there was undissolved sugar in the bottom of the fermenter. I am not sure how much. The fermentation went well to SG 1.015 and then stalled. It went slowly down to 1.012 after the addition of the new culture  then stuck tight. I might have a high alcohol problem? What do you think. Can I get it going again with a high tolerant alcohol yeast? What do you recommend? Dr. P
Hello Dr. P,
Your suspicions of too much sugar may very well founded, but quite often it is a combination of issues that are working in concert to create a stuck fermentation. I would also look closely at the temperature of the wine. If it is below 70 F. I would try to get it up to at least 74 F. to make the wine yeast “happier”. This small change in temperature may not seem like much, but it can make a big difference in the way the your homemade grape wine ferments.
If the temperature seems to be okay you might also want to look at the “Top 10 Reasons For Fermentation Failure” listed on our website. This article lists eight other possible reasons that may be at work here. One of them may help to get your wine brewing again.
If too much sugar still appears to be the only problem, you can try adding 3 or 4 packs of Red Star Pasture Champagne Yeast to the batch. This won’t be two much wine yeast since the pack you added before multiplied itself to about 150 times the original amount. Hopefully, this new wine yeast will be able to multiply as well. Pasture Champagne yeast has a better tolerance to high alcohol and cooler temperature and may be enough to get your homemade grape wine going again.
If you want, you can put the wine yeast in a small amount of the wine first… say a pint. Add an 1/8 teaspoon of Yeast Nutrient and a tablespoon of sugar to the mix and see if you can get that to show some activity. Keep the jar covered with a paper towel or similar. Once any activity peaks, add it to the rest of the wine. This normally takes 1-1/2 to 2 days to happen. If your not sure its peaked or not, pitch it into the wine anyway.
Happy Wine Making
Customer Service at E. C. Kraus
Ed Kraus is a 3rd generation home brewer/winemaker and has been an owner of E. C. Kraus since 1999. He has been helping individuals make better wine and beer for over 25 years.

0 thoughts on “My Fermentation Has Too Much Sugar. What Should I Do?

  1. I followed a one gallon recipe a simple one with yeast sugar and cam den tablets recipe said four lbs sugar for I gallon so I used twenty lbs for five gallons not fermenting can I fix or dump it and start over?

    • Mark, there is no need to dump the wine. What you need to do is determine why the wine is not fermenting, then you can make the corrections needed to get the fermentation going. Below is a link to an article that covers the most common reasons for fermentation failure. I would take a look at the article to see which reason applies to your situation.
      Reasons For Fermentation Failure