Cytological and compositional evaluation of white asparagus spears as a function of variety, thickness, portion and storage conditions

An evaluation was made of the degree of toughening of asparagus during its storage through a study of the morphological and cellular differences of the xylem vascular bundles as a function of the variety, thickness and portion of the asparagus spear. Light microscopic examinations were carried out to determine the thickness of the cell wall to quantify the extent of the toughening. At the same time a study was made of the fractions of dietary fibre of the asparagus spear by means of chemical extraction techniques. Statistically significant differences were observed in both methods between varieties, thicknesses and portions of the asparagus spear. Different factors such as variety, degree of maturing, portion of spear, moment of harvesting, and type and time of storage have an influence on the toughening of white asparagus that should be taken into account in order to standardise its quality.