Determination of phytochemical composition and antioxidant capacity of 22 old apple cultivars grown in Poland

Abstract

The basic chemical composition, polyphenols and antioxidant capacity in 22 old apple cultivars grown in Poland were determined. Fruits were analyzed for contents of individual polyphenolics with the ultra-performance liquid chromatography photodiode detector-quadrupole/time-of-flight mass spectrometry (UPLC-PDA-Q/TOF–MS) method, sugar with the high-performance liquid chromatography–evaporative light scattering detector (HPLC-ELSD) method, and antioxidant capacity with the ABTS and FRAP radical method. A total of 29 bioactive compounds, including 26 polyphenolic compounds (7 flavan-3-ols, 2 dihydrochalcones, 4 anthocyanins, 5 phenolic acids, 8 flavonols) and 3 triterpenoids (ursolic, betulinic and oleanolic acids), were identified in fruits. All the apple cultivars were found to be rich in polyphenols [average 2139.21 mg/100 g dry matter (dm)], especially phenolic acid (average 694.12 mg/kg dm), flavan-3-ols (average 1259.80 mg/kg dm), flavonols (average 106.78 mg/kg dm) and triterpenoids (average 2552.20 µg/g dm), particularly ursolic acid (average 2234.50 µg/g dm), with high ABTS and FRAP capacity (average 72.14 and 46.77 µmol Trolox/100 g dm). The apple cultivars were also found to be a good source of pectins (average 1.19%), acids (average 0.67%) and sugars (average 9.11 g/100 g).