Brix

Degrees Brix is a measure of the dissolved solids in a liquid, based on its specific gravity, and is commonly used to measure dissolved sugar content of a solution. One degree Brix is the concentration of one unit mass of solute in 100 units mass of solution, thereby representing the strength of the solution as percentage by mass. If the solution contains dissolved solids other than pure sucrose, then °Bx only approximates the dissolved solid content. For example, when creates two solutions, one with equal volumes of salt and water and one with equal volumes of sugar and water, the number of degrees Brix of the salt solution is higher than that of the sugar solution because the salt is denser. The unit °Bx is traditionally used in the wine, sugar, carbonated beverage, fruit juice, fresh produce, maple syrup, and honey industries. The degree Brix is also used for expressing concentrations of water-based cutting fluids for metalworking processes. Concentration of dissolved solids can also be measured by using a refractometer, but different solutes affect refractivity differently, and the refractivity is not directly correlated with the specific gravity of the substance, so to infer concentration of any particular substance the correlation between refractivity and concentration for the specific substance must be known.

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