saccharimetry

from The Century Dictionary.

• noun The operation or art of ascertaining the amount or proportion of sugar in solution in any liquid.

from the GNU version of the Collaborative International Dictionary of English.

• noun The act, process or method of determining the amount and kind of sugar present in sirup, molasses, and the like, especially by the employment of polarizing apparatus.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun The measurement of the sugar content of a liquid, especially with a saccharimeter