multi-elemental ed-xrf determination in dehydrated bouillon and sauce base products

This work describes a quick and easy method for the quantification of a series of macroelements (na, mg, p, cl, k, and ca) and trace elements (fe and zn) by energy-dispersive x-ray fluorescence (ed-xrf). the method was developed and validated using commercial dehydrated bouillon and sauce base products. all samples were systematically powdered and analyzed by reference methods (i.e., potentiometry for chloride and inductively coupled plasma-atomic emission spectroscopy (icp-aes) for other elements) and by ed-xrf. a calibration set of 15 samples was selected to cover uniformly the concentration range of each element, and their reference method values were used to calibrate the ed-xrf device. a second validation set, composed of 26 additional samples, was then analyzed as though they were unknown samples. during this validation step, the elemental concentrations obtained by ed-xrf were systematically evaluated against those obtained from the reference methods. for the eight investigated elements, the ed-xrf method was found to be comparable to the reference one; furthermore, the bias between both methods was found to be not significantly different from 0. for the macroelements, the relative uncertainties rsd(u) were found to be lower than 20%. these results have demonstrated that ed-xrf is a quick and reliable method for the quantification of the listed elements in dehydrated bouillon and sauce base products. the capability to accurately measure trace elements (below 20 mg/kg), while also being able to measure a concentration of several tens of gram per 100 g of nacl, makes ed-xrf a perfect tool to check the correct addition of premixes and also to ensure the correct claim of macroelements, respectively.