Swiss analytical instruments company Metrohm has announced a new process for determining the presence of sodium in foods.
Thermometric Endpoint Titration (TET) is, says Metrohm, a simple, rapid and robust method and a viable alternative to spectroscopic techniques, or argentometric titrimetry, which are either expensive, demanding of considerable skills, or produce unacceptable results. On the other hand, notes the company, TET can be automated, is suitable for routine process control, and has been successfully used to analyse foods ranging from dairy products, instant noodles, cheese, canned fish, dry snack food, sauces, soups, and more. More information on TET and its practical use is available from an article recently published in Journal of Agricultural Chemistry and Environment.
Sample preparation for analysis by TET is said to be straightforward. Users must simply make sure that the analyte is fully liberated from the sample matrix, that the fluid containing the analyte is sufficiently mobile, and that there are no inferences from other constituents present in the solution. Usually, appropriate comminution and dilution of the sample are all that is required.
TET shares with other titration techniques the use of a sensor to detect the endpoint of the titration reaction. In the case of TET, the sensor is a thermometer. Because it relies merely on a change of solution temperature to find the endpoint, says Metrohm, there is no need to calibrate the sensor. Sensor maintenance is minimal, and it is normally stored dry between titrations.
