This is a technique type question and something that I have been wondering about for a while. When I make wines from juices, tinned fruit or packaged fruit, the sugar content is listed on the labels so I can work out how much sugar to add to get the results I want. If I am using just juices I can take a hydrometer reading to check I have the S.G. I want. However, if I use picked or loose fruit I don't know how much sugar is contained so I have to guess. If I add this fruit to juices and/or water in a fermentation bin, using a hydrometer right at the start won't tell me how much sugar is still in the fruit as it won't have been released. Therefore I risk adding too much or too little sugar. In fact last year I did add too much sugar and ended up with an extremely sweet wine. I ended up blending with another very dry wine, which happily worked very well. Is there a way I can do better than just guess the sugar content of a given fruit?