This method describes how to determine the total dry residue through evaporation. The total dry residue is defined as the sum of the dissolved and undissolved substances, excluding those that are volatile under the conditions of the analysis. For water with a high hydrogen carbonate (bicarbonate) content, the total dry residue can be considerably lower than the original salt content, since hydrogen carbonates are transformed into carbonates during evaporation, thus liberating H2O and CO2 in the process.
Water intended for use as an ingredient in the production of beer (brewing liquor) or other foods
A specified quantity of water is evaporated, and any remaining moisture is subsequently eliminated in a drying oven. The dry residue is then weighed.