Thanks Mike A.
We get your question a lot: My wine is done fermenting, but the hydrometer is reading no alcohol content. What happened?
Well, I’ve got some great news. It is extremely likely that there is not a problem with the wine. It fermented just fine, and it does have plenty of alcohol in it.
It is much more likely that you are interpreting the hydrometer readings incorrectly. It happens all the time and stems from the fact that the wine hydrometer is a backwards instrument when it comes to reading alcohol content. All that’s needed is a little clarification, and I think you’ll see what I mean.
To determine the alcohol content of any wine you must take more than just one reading with the hydrometer. You must take two readings and compare them – one before the fermentation begins and another one after. For example, a typical beginning reading on the wine hydrometer’s alcohol scale would be 13%. The typical ending reading might be 0%. If this were the case, the wine would have 13% alcohol.
Another point is that the scale is actually not call an alcohol scale. It is called a Potential Alcohol scale. At any given time this scale can tell you how much alcohol can be made with the sugars that are still currently available in the wine must. What it cannot tell you is how much alcohol is in the wine with just that one reading.
In your case, the potential alcohol scale is reading close 0% alcohol content because there is no sugar left to make more alcohol. The sugar has already been consumed by the wine yeast and fermented into alcohol.
If you would liked to read more about why your wine hydrometer is reading no alcohol content, the link will take you to some more detailed information about this: Hydrometer Scales And What They Mean.
Happy Wine Making,
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.