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If a water sample is run through a strongly acidic cation exchanger, all of the cations are replaced with hydrogen ions, thus producing the corresponding free acids in equivalent quantities (total mineral acid value). Since the carbonates and bicarbonates are transformed into carbon dioxide and therefore escape determination, their content must be determined through titration with acid to a pH of 4.3 (m value).

Since analyses for determining the concentrations of sodium and potassium ions in water require considerable effort, and these ions are not very relevant for evaluating the suitability of water for the processes of brewing and malting, a simple calculation will suffice. The difference in the concentrations of anions and cations in the water is determined, allowing the calculation to be performed under the assumption that only sodium ions are present in the water.

Hydrogen peroxide oxidizes iodide to iodine, which is reduced by sodium thiosulfate (Na₂S₂O₃) and recalculated as hydrogen peroxide.

If the sample contains other peroxide-containing disinfectants in addition to hydrogen peroxide (H₂O₂), the method T-757-01-032 Peracetic-acid-based-disinfectants must be used.

Sodium in wort is measured using the AAS technique by directly aspirating the diluted sample into an acetylene oxygen flame; the measurement is made at 589 nm.

Inductively coupled plasma optical emission spectroscopy (ICP-OES) is a fast and reliable method for the laboratory analysis of metals. Inductively coupled plasma (ICP), a high frequency field of ionized gas, serves as a medium for atomizing and exciting the substances found in samples. Liquid, dissolved or aerosol samples are injected into the ionized gas stream. In emission spectroscopy, ICP can be used in conjunction with a number of optical and electronic systems either simultaneously or sequentially in multi-element spectrometers. In the plasma, the atoms and ions are excited to a higher energy state bringing about the emission of electromagnetic radiation (light), primarily in the ultraviolet and visible region of the spectrum. Metals ordinarily occur as ions in the temperature range typical for ICP of 6000 to 10000 K; however, non-metals and metalloids are only partially ionized.

ICP-OES operates within a very wide range. This usually encompasses six orders of magnitude in concentrations smaller than μg/l up to g/l, depending upon the element and the concentrations used for the set of analysis data. With ICP-OES, beer and wort can also be analyzed without prior processing of the samples, in contrast to AAS. Methods for determining the following in beer and wort will be described below: Al, B, Ba, Ca, Co, Cu, Fe, K, Mg, Mn, Mo, Na, P, Si, Sr, Sn and Zn.

The sodium in beer is determined using atomic absorption spectroscopy (AAS) by directly aspirating the diluted sample into an acetylene oxygen flame. The measurement occurs at 589.0 nm. A cesium chloride addition reduces interference from the ionization of compounds in the beer matrix.