The effect method of preservation on selected bioactive compounds and antioxidant activity in blackthorn fruits (Prunus spinosa L.)

The effect of freezing (M), freeze drying (L) and convection drying (S) of blackthorn fruits on the content of selected bioactive compounds and antioxidant properties compared to the control sample – fresh fruit (PK), was tested. Changes in the content of flavonoids, anthocyanins, pectins, general acidity and the ability to reduce the DPPPH radical, were determined. The obtained results showed that the freeze-dried fruits had the highest content of anthocyanins and flavonoids, respectively 0.07 and 0.17%. Pectin contents in freeze-dried and convectively dried fruits were similar at the level of 1.66 and 1.64% as well as for acidity respectively 0.076 and 0.071 g·100 g–1 infusion. Frozen fruits did not differ significantly compared to the control in terms of the content of anthocyanins, flavonoids, pectin and acidity. The highest scavenging capacity of free radical DPPH was characterized by the infusion obtained from fresh fruits