MINERAL-CONTENT MODIFICATIONS DURING RIPENING OF ASPARAGUS (ASPARAGUS-OFFICINALIS, L)

The essential elements: calcium (Ca), magnesium (Mg), sodium (Na) pota ssium (K) and phosphorus (P) were analyzed in fresh asparagus to deter mine the effect of the ripening of the asparagus on the mineral conten t. Asparagus samples were classified in two groups by diameter (<11 mm and >14 mm). Asparagus from a sample group with the same diameter wer e divided into two portions (aapical and basal) according to distance from the tip. The concentrations of calcium, magnesium and phosphorus increased with the ripening process of the asparagus while the content of sodium decreased when the white asparagus turned into a green ripe ning state. No significant differences were established for potassium. The green ripening state was the group with the greater concentration of calcium, magnesium and phosphorus. Statistically significant diffe rences (p <0.001) were observed between portions of asparagus (tip and rest of stem) in the contents of the five mineral elements analyzed. The levels of mineral elements investigated increased notably in the t ip of the asparagus with the exception of sodium and potassium of whic h the levels in the apical portion decreased or hardly modified. The v ariance analyses determined statistically significant differences (p < 0.001) in the concentration of magnesium, sodium and phosphorus betwee n asparagus diameters (<11 and >14mm) and no significant differences ( p>0.05) were found for calcium and potassium. The mean element levels were (mg/kg dry weight):Ca=3240+/-1186; Mg=1818+/-490; Na=368+/-86; K= 37297+/-4167 and P=6809+/-2481.