Trends and nutritional significance of mineral content in fresh white asparagus spears.

Variations in the copper, iron, zinc, manganese, calcium, magnesium, sodium, potassium and phosphorous content of fresh white asparagus (Asparagus officinalis, L.) as a function of the spear portion and the differences between varieties (Desto and Cipré's) and thicknesses (< 11 and > 14 mm) of asparagus were investigated. The mineral elements studied showed significant changes between the ten portions into which the spears were cut, with lower concentrations, except for sodium, occurring in the asparagus portions furthest away from the tip of the spear. These changes between portions signified a greater nutritional value of the apical spear area (6 cm from the asparagus tip) according to the higher percentages of mineral RDAs supplied in the apical portions. The varieties and thicknesses of white asparagus investigated showed this diminishing distribution of the mineral content throughout the spear and displayed significant differences for the majority of the mineral elements between varieties and thicknesses, although these differences were minimal and did not have any nutritional significance since the percentages of mineral RDAs supplied were similar. Nutrient density was well over 100% for all the elements, except for sodium, and these results indicated that fresh white asparagus, if consumed in sufficient quantities, contributes substantially to the intake of these mineral elements.