Karl Fischer titration
Automated moisture analysis of chocolate, no problem with Metrohm.
For several reasons, the water content of chocolate is of crucial importance and has to be accurately determined. The poster in the link compares an automated version of the Karl Fischer titration (KFT) using the sequential addition of various solvents with the widespread manual titration at elevated temperatures using a chloroform/methanol mixture.
The water contents determined by the two procedures show excellent agreement. However, manual titration requires labour-intensive sample preparation, the side reactions are difficult to quantify and hazardous halogenated solvents have to be used.
In contrast, automated KFT is straightforward, uses non-hazardous solvents, allows to quantify the side reactions and is easily applicable to water determinations in sugar- and fat-containing matrices.