Determination of total water and surface water in sugars

A clear distinction between differently bound water fractions by drying techniques is usually not possible. The Karl Fischer titration was used to achieve such a differentiation. As this technique is based on a chemical reaction, water is only determined when it comes into direct contact with the reagents. Surface water can therefore be detected easily. To limit the determination to this fraction, dissolution of the sample must be avoided. If, on the contrary, the total water is to be determined, the sample must either be dissolved completely or measures must be taken to liberate the water from the sample matrix. The aim of this work was to find titration parameters and working conditions that allow the distinction between the total water content and the surface water of sugars.