4. Conclusions
In this study, a new multiple chemometric response function
was established to qualitatively and quantitatively evaluate the
analytical signals obtained during the multivariate optimization
of the method proposed for the direct determination of cadmium
concentrations in vinegar by ET AAS.
The multiple chemometric response function generated models
that were validated and had good fits.
The direct method proposed is precise and accurate and has a
limit of quantification that is sufficiently low for the determination
of cadmium concentrations in vinegar.
The use of cold finger allows a complete digestion of vinegar
samples using nitric acid and hydrogen peroxide for the determination
of cadmium.
The cadmium contents of the six analysed samples were lower
than the maximum limit allowed for foods by Brazilian regulations.
The determination of cadmium in certified reference material of
bovine liver demonstrated that this method can be employed for
quantification of cadmium in others matrices.