Pulsed Electric Field Treatment of Berry Fruit Seeds: Effect on Phenolic Compound Recovery

Abstract

Pulsed electric field (PEF) technology represents a promising non-thermal method for enhancing the extraction of bioactive compounds from plant matrices. This study investigated the influence of PEF treatment on the bioactive compounds composition of aqueous extracts obtained after processing blackcurrant, redcurrant, chokeberry, raspberry, and blackberry seeds. The seeds were treated at 8 kV or 10 kV electrode voltage, and 50 kJ/kg energy input, and the resulting extracts were analyzed for total polyphenol content (TPC), antioxidant capacity (ABTS and DPPH assays), anthocyanin composition (HPLC-DAD), and color parameters (L*, a*, b*). The PEF treatment significantly enhanced the release of polyphenols, anthocyanins, and antioxidant compounds, particularly in chokeberry, raspberry, and blackberry seed extracts. Extracts obtained after PEF treatment exhibited higher TPC, in a range between 0.57 and 3.00 mg GAE/g, and higher radical scavenging activity in a range 2.33–35.07 µmol TE/g in ABTS assay and 1.07–12.27 µmol TE/g in DPPH assay. Also, more intense red coloration was determined, confirming that electroporation facilitated pigment and phenolic migration into the aqueous phase. These findings demonstrate that PEF is an efficient and solvent-free intensification technique for the valorization of berry by-products, generating aqueous fractions rich in natural antioxidants and colorants that support circular and sustainable fruit-processing practices.