Development of functional edible oils enriched with pistachio and walnut phenolic extracts

The purpose of this research was the development of functional edible oils with potential health promoting effects, enriched with phenolic-rich extracts obtained from pistachio and walnut. A high phenolic content, 10860 mg/kg and 7030 mg/kg in walnut and pistachio kernels respectively, with a corresponding strong radical scavenging effect (DPPH, 106 and 20 mmol/kg Trolox) were found. The remarkable antioxidant capacity of the phenolic-rich extracts prepared form walnut (255 mol/kg Trolox, measured by DPPH, 1500 times higher than its kernel) and pistachio (13 mol/kg, 630 times higher) makes them good candidates to evaluate their potential as bioactive ingredients. In the different enriched edible oils studied, a phenolic concentration of 340-570 mg/kg has been reached, showing the functional oils a great antioxidant activity, which was apparently much higher when walnut extracts were employed (e.g. 54 mmol/kg Trolox, as DPPH).