Abstract
•Hydrolysates of PEF-treated OdEW at pH 4 had enhanced antioxidant activity.•Hydrolysates of PEF-treated OdEW at pH 4 suppressed interleukin-8 production.•Hydrolysates of PEF-treated OdEW at pH 4 had similar bioactivity to that achieved by heating at 80 °C.
This research investigated the effects of pulsed electric fields (PEF) (1.4–1.7 kV/cm, 653–695 kJ/kg) and heating (60 and 80 °C for 10 min) at different pH (4, 5, 7, and 9) on the antioxidant and anti-inflammatory activity of ovomucin-depleted egg white (OdEW) after in vitro gastrointestinal hydrolysis. PEF and heating (80 °C for 10 min) at pH 4 enhanced the antioxidant activity of the whole hydrolysates, chemically determined using DPPH and ORAC assays. Furthermore, the anti-inflammatory activity of protein hydrolysates was assessed in lipopolysaccharide-stimulated HT-29 cells using ELISA assay. PEF and heating at pH 4 enhanced the anti-inflammatory activity of the whole hydrolysates dose-dependently. Hydrolysates at 1 mg/ml showed similar inhibition (35.5% and 35.9%) of interleukin-8 production, due to PEF treatment and heating (80 °C for 10 min), respectively. Results indicated that prior PEF treatment can analogously enhance both antioxidant and anti-inflammatory activity of OdEW hydrolysates to heating, with potentially reduced thermal input.