Sugar

Another raw material that can be very useful is sugar. Adding sugar to the juice is not an uncommon industry practice in the East, and will cause the finished wine to have a higher alcohol content. The formula for adding sugar is detailed in the procedures section under sugar adjustment formula.  By measuring the initial juice sugar level, the winemaker can calculate how much sugar to add to ultimately end up at a given alcohol level (multiply °Brix of sugar by 0.55 to estimate the final alcohol level). These estimates are subject to some error, but they generate a ballpark figure. This can be used to produce a consistent level of alcohol from year to year from grapes in which the natural sugars will vary.