Mineral composition and heavy metals content of sweet chestnut fruits in five natural populations from central Croatia

In recent years the consumers have been showing an increased interest in chestnut fruits because of their nutritional qualities and potential beneficial health effects. Since the information about nutritional composition of the fruits from the natural populations is still limited the aim of this stud was to analyze their mineral content. Nuts were sampled in five natural populations, from the central area of sweet chestnut distribution range in Croatia. Each population was represented with five trees. Macro and micro elements (K, Ca, Mg, Na, Fe, Zn) and heavy metals (Pb, Cd, Hg, As) were determined by atomic absorption spectrophotometry using a Varian SpectrAA 220 device. Univariate and multivariate statistical techniques were used to evaluate the differences among populations. Chestnuts of all five populations contained K, Ca, Mg, Na, Fe, Zn in average 613.96, 35.17, 29.99, 3.69, 1.37 and 0.70 respectively. The obtained results for heavy metals content provided evidence that the concentrations were lower than the toxic law limits. An analysis of variance showed significant difference between populations regarding each mineral. The study also confirmed a trend of population variations according to the eco-geogrphic principle.