Multivariate characterization of fresh tomatoes and tomato-based products based on mineral contents including major trace elements and heavy metals

The contents of five minerals (Na, K, P, Ca and Mg) and nine trace elements (Se, Fe, Zn, Cu, Mn, Mo, Pb, Cd and As) have been determined in 80 fresh tomato and tomato-based products: tomato paste, tomato juice, minced tomato, tomato puree, grated tomato and dried tomato. Analyses were performed by inductively coupled plasma mass spectrometry (ICP/MS). In order to characterize and classify the samples, chemometric analyses were performed by combining principal component analyses(PCA), hierarchical cluster analyses (CA) and variance analyses (ANOVA). The application of multivariate analyses tended to categorize samples according to product variety, establishing nutritional relationships of products and identifying healthy nutritional sources. The results of the mineral measurements revealed that tomato juice and minced tomato are the best substitutes for fresh tomato. Moreover, there were considerable differences in trace element composition among the tomato samples. Heavy metal levels varied among samples.