A new HPLC stationary phase has been applied to the analysis of phenolic acids and flavonoids with diode array and mass
spectrometric detection. The separation of 26 standard compounds was achieved within 1 h. The stationary phase displayed
excellent resolution especially of flavonol glycosides. The analytical system has been used for the determination of phenolic
compounds in apple pomace and apple juice, and in extracts of pear fruits of different cultivars. Apple pomace was found to
be a promising source of phenolics. However, yields are affected by the drying conditions applied. Furthermore, the
applicability of the analytical system for the authenticity control of apple and pear juice was demonstrated by determination
of characteristic quercetin and isorhamnetin glycosides, and dihydrochalcones, respectively. Since isorhamnetin-3-glucoside
was present in all pear cultivars investigated, the usefulness of arbutin as a specific marker of pear products appears to be
doubtful. 2001 Elsevier Science B.V. All rights reserved.