The qualitative analysis of the aqueous extract showed the presence of polyphenolics belonging to different chemical groups: flavan-3-ol derivatives (catechin and procyanidin B3), gallic acid derivatives (gallic acid, ethyl gallate and pentagalloylglucose) and depsides (ellagic acid). The content of total phenolic and procyanidin in extracts depended on the duration of seeds storage and varied from 469 to 388 mg/g and from 436 to 372 mg/g, respectively. The HPLC quantitative analysis of the three main compounds showed that their content varied from 3.7o to 6.18 mg/g for gallic acid, from 23.43 to 18.91 mg/g for (+)-catechin and from 12.5 to 8.02 mg/g for pentagalloylglucose. During seeds storage, the quantity of pentagalloylglucose in extracts decreased by about 30%, while gallic acid content increase was about 30%. The quantity of (+)-catechin has changed less significantly. The scavenging potential of the extracts determined with the DPPH method correlated with the higher concentration of pentagalloylglucose.