A chemical study of the mineral fraction of Tarragona hazelnuts (Corylus avellana L.)

Mineral contents and phytic acid were determined in the main varieties of Tarragona hazelnuts (Negret, Pauetet, Gironell, Culpla, Morell and Grifoll). Macro- (K, Mg, Ca, and Na) and micro elements (Cu, Mn, Fe, Zn, and Cr) were quantified using atomic absorption spectrophotometry, on dry-ashed samples. N, P, and phytic acid were determined using Kjeldahl method, colorimetric vanadium-molybdate, and HPLC system. respectively. The analysis of variance showed significant difference (P less than or equal to 0.05) in N, Mn and Na contents between farming methods. Only K content showed significant difference (P less than or equal to 0.05) between varieties. The correlations between mineral contents were calculated, but only the Cu/Zn correlation was greater than the Pearson-Lee limit (r=0.660, P less than or equal to 0.05). The percentage of phytic acid is low (0.17 g/100 g). The mineral intake that hazelnut consumption could represent was evaluated with regard to the Recommended Dietary Allowance (RDA).