Supercritical fluid extraction prior pulsed electric fields to improve high-added-value compounds recovery from salmon side streams: Evaluation of protein, bioactive peptides and minerals

Abstract

A sequential extraction process combining supercritical fluid extraction (SFE: 25.0 MPa, 75 min, 50.0 °C, and 10.0 mL/min flow) with pulsed electric fields (PEF: 3.0 kV/cm, 300 kJ/kg for head/backbones, 124.8 kJ/kg for viscera) or conventional extraction (CE: 60 min, 300 rpm) was optimized to enhance the recovery of high-added-value compounds, including proteins, bioactive peptides, minerals, heavy metals, and total antioxidant capacity (TAC) from salmon side streams. Protein levels increased notably with PEF, particularly in viscera liquid extracts, reaching 15.5 g/100 g. Bioactive peptides displayed anti-inflammatory, immunomodulatory, anticancer, hypolipidemic, and antithrombotic potential. Viscera liquid extracts showed high TAC (402.8 and 3263.6 μM). ICP-MS analysis revealed PEF treatment helps solid matrices retaining more minerals and heavy metals. Principal component analysis (PCA) on proteins, peptides, minerals, and heavy metals elucidated PEF's impact, identifying two main components affecting the salmon matrix and extract composition.

Keywords: Bioactivity peptides; Mineral and heavy metal; Protein; Pulsed electric field (PEF); Salmon solid matrices and liquid extracts.