Differentiation of tomatoes based on isotopic, elemental and organic markers.

In this study, 41 tomato samples were investigated by means of stable isotope ratios (δC, δO and δH), elemental content, phenolic compounds and pesticides in order to classify them, according to growing conditions and geographical origin. Using investigated parameters, stepwise linear discriminant analysis was applied and the differences that occurred between tomato samples grown in greenhouses compared to those grown on field, and also between Romanian and abroad purchased samples were pointed out. It was shown that Ti, Ga, Te, δH and δC content were able to differentiate Romanian tomato samples from foreign samples, whereas Al, Sc, Se, Dy, Pb, δO, 4,4'-DDT could be used as markers for growing regime (open field vs.