Beaume (BE) salt concentration means what?

The saturated brine which is normally used for salting cheese occasionally produces too hard a rind, but this can be counteracted by using a weaker solution. The solution should , however, contain at least 20 % salt, corresponding to 19 degree Beaume. The strenght of the brine should be checked every day, otherwise there is a risk of the solution becoming too weak. When this happen, the cheese protein exuded trough the whey will quickly decompose, and the increase in the growth of bacteria will cause defects not only in the rind but also in the interior.
The strenght of the brine should be measured with a hydrometer specifying Beaume degree. When the brine has been in use for a certain time, the hydrometer will show a deviation of 1 - 2 Beaume degree because the substances being dissolved in the brine. That is to say, in practice, when measuring the strenght of a 2 - 3 months old brine solution, Beaume degree can be considered equal to the salt percentage.