Brix is the system used in the United States to measure the sugar content of grapes and wine. You often see it mentioned on the back label of California wines, though few consumers know what it means. Here's the scoop: Each degree of Brix is equivalent to one gram of sugar per 100 grams of grape juice. The higher the reading, the greater the sugar content and, ergo, the higher the potential alcohol level. Most grapes are ready to be harvested when their Brix level reaches 20 to 25 degrees, and since 55% to 60% of the sugars are converted into alcohol during fermentation, you can deduce the amount of alcohol that should result (25 x .55 = 13.75% alcohol). FYI, the system was named after German inventor A. F. W. Brix, though German winemakers use a different scale called "Oechsle." Australia and most of Europe, including France, use a similar method called the "Baumé" scale.