Veränderungen phenolischer inhaltsstoffe des apfels während wachstum und reife

Developmental changes in the phenol concentrations of apple fruit skin and leaves were determined. Phenolic levels decreased during growth and maturation of fruits and leaves with respect to their ontogenesis but the single compounds did not behave uniformly. It is obvious that the pool of hydroxycinnamic acids as represented by chlorogenic acid and the monomeric flavanols decreased in favour of flavonols and procyanidins. Furthermore, the decreasing ratio epicatechin/procyanidin B2 from spring to autumn could be interpreted as an enhanced oligomerization during the growing season. The last step of this process may be the formation of insoluble proanthocyanidins.