Refractometer for Testing Sugars and Corn Syrups

Hi, I just bought the Palm Abbe refractometer with 5 scales from you. I have tried it at our office but I cannot get it come to the right results. We are only going to measure total sugar content and alcohol in wines (finished wines). I have calibrated it with distilled water and it seems to measure water to 0.0 every time which is ok. As soon as i measure alcohol in red wine it always shows too high digits – up to 18-20% ABV and the sugar is always too high. What may the problem be in this case?

The problem is that you cannot directly measure the alcohol content in finished wine using a refractometer. Once fermentation begins ethanol and the residual sugar interfere with each other and prevent an accurate reading of either sugar content or alcohol content. The best method for determining the alcohol content in the wine is distillation. There are also some good methods of estimating alcohol and sugar content during fermentation and later in the finished wine. For more information, download a copy of our free guide, “Using Refractometers to Increase the Efficiency of Vineyard Management and Winemaking “Using Refractometers to Increase the Efficiency of Vineyard Management and Winemaking.”

How accurate is your refractometer when alcohol is present? Can I measure R.S. [residual sugar] in wine? thanks

Alcohol and sugar interferes with each other when measuring finished wine with a refractometer. You cannot measure the alcohol content in a finished wine directly using a refractometer, nor can you directly measure the residual sugar content. There are however, a couple of tricks that you can use to determine alcohol content and residual sugar content using a refractometer. These methods and more are discussed in detail in our technical bulletin, “Using Refractometers to Increase the Efficiency of Vineyard Management and Winemaking.”