Quantitative analysis of sodium concentration in condiments, soft drinks, and mineral water by external standard 23Na-qNMR

Sodium is essential for human health, but excessive intake can lead to hypertension. Accurate sodium labeling in foods is critical due to increasing health awareness. This study investigated the use of 23Na nuclear magnetic resonance spectroscopy (NMR) for sodium quantification in condiments, soft drinks, and mineral water. In this study, external standard quantitative 23Na-NMR was used to measure sodium concentrations. Key steps included sample preparation, 90° pulse width calibration, and linewidth evaluation. The results showed that 23Na-NMR can accurately quantify sodium concentrations over a wide range, with good agreement with ion electrode methods. The results demonstrated that 23Na-NMR is a reliable method for the quantification of sodium in various liquid foods.