The values obtained with the conventional gravimetric method using a drying oven to determine moisture are generally too high. The KARL FISCHER titration method is more reliable for delivering accurate values.
Hop extract intended for use in beer brewing or elsewhere in the food industry
SO2 in the Karl Fischer solution creates an ester with methanol, which is neutralized through a reaction with a base. The anions of methylated sulfuric acid are the reactive component in the chemical reaction. In the water titration, the methyl sulfite anions are oxidized by iodine to form methyl sulfate. The endpoint can be determined either by a color change (addition of a starch solution) or electrochemically.