Determination of the fructose-glucose ratio
High-fructose corn syrup (HFCS) is a sweetener made from corn starch. In a first step, the starch is broken down in its glucose monomers by enzymes. After that, the enzyme D-xylose isomerase converts some of the glucose into fructose to make HFCS. By using refractometry in combination with polarimetry, it is possible to determine the approximate ratio of fructose and glucose.