Nutritional evaluation of mineral content changes in fresh green asparagus as a function of the spear portions

Abstract

Changes in the copper, iron, zinc, manganese, nickel, chromium, calcium, magnesium, sodium, potassium and phosphorus content of fresh green asparagus (Asparagus officinalis L) according to the portion of spear considered and differences existing between varieties (Mary-Washington and UC-150) and thicknesses (<11 and 14 mm) asparagus were investigated. Using a three-factors (portions, varieties and thicknesses) ANOVA and the Scheffe multiple range test (P < 0.05), statistically significant differences (P < 0.001), between the 10 portions in which the spears was cut, were observed for the 11 mineral elements investigated and the more apical portions presented, except for sodium, a higher mineral content which showed a generalised decrease when the portions were furthest away from the asparagus tip. By multivariate study of cluster between portions, the 0 apical portion (asparagus tip) was grouped separately to the rest of portions of the spear. These changes between portions involved a greater nutritional value of the apical zone spear in basis to the nutritional profile established for the mineral content. The diminishing distribution of the mineral concentration throughout the spear was also observed in the varieties and thicknesses of fresh green asparagus investigated which showed significant differences in this mineral content without these changes involved any nutritional significance since the mineral RDAs supplied were similar. Nutrient density percentages of the total fresh green asparagus are much higher than 100% for all the elements studied, except for sodium, and therefore, if the fresh green asparagus is consumed in sufficient quantities, contributes substantially to the intake of these mineral elements. © 1999 Society of Chemical Industry