HIGH-PERFORMANCE LIQUID-CHROMATOGRAPHY WITH DIODE-ARRAY DETECTION FORTHE DETERMINATION OF PHENOLIC-COMPOUNDS IN PEEL AND PULP FROM DIFFERENT APPLE VARIETIES

Quantitative analysis of phenolic compounds from four apple varieties (Golden and Red Delicious, Granny Smith and Green Reineta) using high- performance Liquid chromatography with diode-array detection was carri ed out. For each variety, both peel and pulp were analysed. The identi fication of phenolic compounds was made by comparing their retention t imes and UV spectra with those of standards. The results revealed diff erences between pulp and peel in all cases studied. The highest levels of phenolic compounds were found in the peel. High levels of catechin s and flavonol glycosides, especially rutin, were found in apple peels . Chlorogenic acid was the major peak in the pulp for all apple variet ies studied except for Granny Smith. Significant quantitative differen ces between the apple varieties were also found, the Golden Delicious variety showing the lowest content of phenolic compounds and Green Rei neta variety the highest. The recovery of phenolic compounds from both peel and pulp was measured in all apple varieties. The values ranged between 95 and 105%, indicating close to quantitative recovery for the method used. (C) 1998 Elsevier Science B.V. All rights reserved.