Labo VinSugar measuring by densitometry
The density of a liquid increases proportionally to its sugar concentration. Furthermore the density depends on the temperature. Several types of densimeters exist, like the Salleron mustimeter, the most used one, which indicates the sugar concentration in g/L of the liquid in which it is dipped. A liquid, whose density is 1.175 will thus indicate 1175 (1000 being the mass of 1 litre pure water). In this software, you can write 1.175 or 1175. Some mustimeters have several scales: one additional scale can indicate the sugar concentration. An important factor is the calibration temperature of the mustimeter (15 or 20° C). This temperature is important, like the temperature of the tested liquid.
It is possible to measure the sugar content of a liquid containing alcohol (e.g. partly fermented liquid or liqueur). In this aim, the alcohol has to be removed. A sample (e.g. 100 mL) of liquid is boiled until evaporation of half its volume. The initial volume is then restored with water. The measurement can then be made.